Fluid jet surgical instruments

ABSTRACT

The invention provides a variety of surgical instruments for forming a liquid jet, which are useful for performing a wide variety of surgical procedures. In some embodiments, the invention provides surgical liquid jet instruments having a pressure lumen and an evacuation lumen, where the pressure lumen includes at least one nozzle for forming a liquid jet and where the evacuation lumen includes a jet-receiving opening for receiving the liquid jet when the instrument is in operation. In some embodiments, the pressure lumen and the evacuation lumen of the surgical liquid jet instruments are constructed and positionable relative to each other so that the liquid comprising the liquid jet, and any tissue or material entrained by the liquid jet can be evacuated through the evacuation lumen without the need for an external source of suction. The invention also provides a variety of surgical liquid jet instruments that are constructed and configured specifically for use in a surrounding liquid environment or a surrounding gaseous environment. The invention also provides a variety of surgical liquid jet instruments that are rotatably deployable from an undeployed position, for insertion into the body of a patient, to a deployed position, in which there is a separation distance between the liquid jet nozzle and the jet-receiving opening that defines a liquid jet path length. The invention also provides surgical methods utilizing the inventive surgical liquid jet instruments, and methods for forming components of the surgical liquid jet instruments.

RELATED APPLICATIONS

[0001] This application is a divisional of application Ser. No.09/313,679, filed May 18, 1999, entitled FLUID JET SURGICAL INSTRUMENTS,and now pending.

FIELD OF THE INVENTION

[0002] The invention relates to surgical instruments for creating aliquid jet and methods for using the instruments in surgical procedures.

BACKGROUND OF THE INVENTION

[0003] Traditionally, many surgical procedures have been performed onpatients using open surgical methods that utilize relatively largeincisions to expose a surgical field. Many traditional methods have alsotypically utilized surgical tools such as scalpels, scrapers, bluntdissectors, lasers, electrosurgical devices, etc., which have poortissue differentiating capability and which can easily cause inadvertentdamage to tissue surrounding a surgical treatment site unless carefullyutilized. Open surgery with such prior art surgical instruments ofteninvolves extensive trauma to the patient, with associated problems oflong recovery periods and potential complications.

[0004] There has been a trend in recent years to perform many surgicalprocedures using less invasive techniques by accessing surgical sitesvia small holes through the skin or through body orifices. Thesetechniques are known as “minimally invasive surgery.” Minimally invasivesurgical techniques commonly employed include endoscopic, laparoscopic,and arthroscopic surgical procedures. Minimally invasive surgicalprocedures are commonly preferred to open surgical procedures for manyapplications because the minimally invasive procedures induce lesstrauma to the patient during surgery and involve, in many cases, fewerpotential complications and reduced recovery time.

[0005] A variety of instruments have been developed and utilized forminimally invasive surgical procedures. Frequently used instrumentsinclude blades and scalpel-type instruments, motorized rotary bladeinstruments, laser instruments, and electrosurgical or electrocauteryinstruments. Typically, these prior art instruments suffer from avariety of disadvantages. For example, the instruments can be slow andlaborious to use, typically they lack the ability to selectivelydifferentiate tissue to be excised from non-target tissue, they tend tohave sizes and/or shapes which make access of many surgical sitesdifficult, and they tend to cause unintended damage to tissuesurrounding the intended target tissue. Most prior art instruments alsorequire the operator to manually remove excised tissue, for example withforceps, or require an external source of vacuum to be applied to thesurgical site, for example via an aspiration tube that is separate fromthe surgical instrument, in order to remove excised tissue. Forapplications such as arthroscopy, where visualization of the surgicalsite is typically effected using an imaging system having a probe suchas a fiber optic probe inserted into the surgical site, the abovementioned prior art surgical instruments also typically make itdifficult to clearly visualize the site of tissue excision within thesurgical field by not effectively evacuating tissue and debris from thesurgical site.

[0006] Instruments that employ liquid jets have also been utilized insurgical procedures for cutting and ablating tissue. Such instrumentshave many advantages over the above mentioned surgical instruments forperforming both open and minimally invasive surgical procedures. Forexample, the cutting or ablating power of the liquid jet may be adjustedor controlled by an operator of the instrument, for example by varyingthe pressure of the liquid supplied to form the jet, to allow forimproved tissue differentiation and to reduce inadvertent damage tosurrounding tissues when cutting or ablating the target tissue. Liquidjet instruments also can avoid the thermal damage to surrounding tissuesthat is often caused by instruments such as lasers and electrosurgicaldevices. In recent years, liquid jet instruments have been utilized fora variety of surgical procedures including open surgical procedures suchas liver resection, endoscopic procedures such as kidney stonedisruption and removal, and arthrectomy procedures for removal ofthrombotic tissue from the vascular system.

[0007] U.S. Pat. No. 4,898,574 to Uchiyama et al. describes a variety oflithotomic devices for insertion into a body cavity, which create afluid jet that is utilized to break up and crush calculi, for examplekidney stones, in the body of a patient. The instruments disclosedtypically include one or more suction channels for removing fluid anddebris. The instruments require that the suction channel be coupled toan external source of vacuum, such as a vacuum pump. The instrumentsdisclosed also typically lack a target or deflector upon which the fluidjet impinges, and, therefore, have the disadvantage of potentiallycausing unintended damage to healthy tissue by misdirection of the fluidjet.

[0008] U.S. Pat. No. 4,913,698 to Ito et al. describes a liquid jetsurgical handpiece designed for crushing and removing brain tumors incerebral surgery. The disclosed instrument includes a liquid jet formingnozzle and a suction tube, which is required to be coupled to anexternal source of vacuum for removal of the tissue and debris excisedby the liquid cutting jet. The liquid jet nozzle is oriented in such amanner that the liquid jet from the nozzle is directed towards aconfronting inside wall of the tip of the suction tube when theinstrument is in operation in order to prevent the liquid jet frominadvertently damaging a non-target tissue.

[0009] U.S. Pat. No. 5,135,482 to Neracher discloses a liquid jetinstrument for removing a deposit obstructing a vessel in a human body.The device is configured as a multi-lumen catheter, which includes apressure resistant duct having a nozzle orifice that creates asupersonic cavitating liquid jet. The liquid jet is directed distallyfrom the instrument to ablate a deposit within a vessel. Someembodiments of the catheter device also include a suction lumen whichcan be coupled to an external source of vacuum for removing liquid anddebris from the vessel. The catheter instruments disclosed do notinclude a deflector or target element to prevent the liquid jet frompotentially impinging upon and causing unintended damage to the vesselor tissue surrounding the deposit to be ablated.

[0010] U.S. Pat. No. 5,318,518 to Plechinger et al. disclose a fluid jetinstrument configured as a catheter for ablation and removal of amaterial or deposit from a body vessel or hollow organ. The distal endof the catheter includes a fluid jet nozzle that directs a fluid jetinto the mouth of a discharging lumen when the instrument is inoperation. The discharging lumen includes a mixing tube and diffuserelement. The fluid jet directed into the discharging lumen creates anaspiration force, due to eductor pump action, which serves to transportfluid and ablated material through the discharging lumen without theneed for an external source of suction. The mixing tube and diffuserelement included in the discharging lumen serve to enhance theaspiration force created by the eductor pump action. The fluid jet canshred or shatter tissue or deposits that lie between the nozzle outletand the inlet of the discharging lumen, and can drive the shatteredparticles into the inlet of the discharging lumen for evacuation fromthe surgical site.

[0011] U.S. Pat. No. 5,370,609 to Drasler et al. discloses a fluid jetthrombectomy catheter for removing a thrombus deposit from thecardiovascular system of a patient. The catheter includes a pressurelumen for transporting a high pressure liquid to at least one jetnozzle, and a relatively large bore evacuation lumen for removing liquidand ablated tissue and debris. In operation, the catheter is configuredto direct at least one liquid jet into the opening of the large-boreevacuation lumen in a direction that is proximal and coaxial with theevacuation lumen. By directing the jet towards the orifice of thelarge-bore evacuation lumen of the catheter, a stagnation pressure isinduced which can propel fluid and debris proximally for removal.

[0012] U.S. Pat. No. 5,527,330 to Tovey discloses a fluid jet cuttingand suctioning instrument configured, in some embodiments, forlaparoscopic insertion into a patient through a trocar. The instrumentincludes a body having a handle, an irrigation tube that includes afluid jet nozzle at its distal end, and an evacuation tube, or in someembodiments a backstop member, positioned to receive the fluid jet.Several of the disclosed embodiments involve an instrument for creatinga fluid jet that is directed transversely to a longitudinal axis of thebody of the instrument. In one embodiment, the instrument includes asliding sheath element that is able to move the irrigation tube andsuction tube laterally with respect to each other to adjust the gapbetween the fluid jet forming nozzle and the inlet of the suction tubeso as to change the length of the fluid cutting jet, when the instrumentis in operation. The instruments described by Tovey have severaldisadvantages for use in many minimally invasive surgical procedures.For example, the shape and design of the irrigation and suction tubesrequires the instrument to be relatively bulky and have across-sectional dimension and shape that is ill suited for inserting theinstrument into confined regions of the body for performing manyminimally invasive surgical procedures. In addition, the instrumentsdisclosed are designed so that an external source of suction must becoupled to the suction tube in order to evacuate fluid and ablatedtissue from the surgical site.

[0013] While the above mentioned surgical liquid jet instrumentsrepresent, in some instances, significant improvements over many priorart surgical instruments for performing open and minimally invasivesurgical procedures, there remains a need in the art to provide simple,inexpensive, liquid jet surgical instruments which have improvedcutting, ablation, and tissue evacuation capabilities, and which havethe ability to be utilized in a wide variety of open and minimallyinvasive surgical procedures. The present invention provides, in manyembodiments, such improved surgical liquid jet instruments, and furtherprovides methods for their use in a variety of surgical procedures.

SUMMARY OF THE INVENTION

[0014] The present invention provides a series of devices related tosurgical procedures utilizing liquid jets for cutting, ablating,sculpting, trimming, etc., tissues and/or materials from the body of apatient. The invention includes, in one aspect, a series of devicescomprising surgical liquid jet instruments for forming a liquid jet, inanother aspect, methods for using the surgical liquid jet instruments,and, in yet another aspect, methods for forming certain components ofthe surgical liquid jet instruments.

[0015] In one aspect, the invention provides a series of surgical liquidjet devices. One device comprises a surgical instrument for use in agaseous or liquid environment having a distal end that is adapted toperform a surgical procedure on a patient and a proximal end that isadapted to be controllable by an operator. The instrument includes apressure lumen that has a sufficient burst strength to conduct a highpressure liquid towards the distal end of the instrument, and thatincludes at least one nozzle providing a jet opening. The instrumentfurther includes an evacuation lumen that includes a jet-receivingopening that has a cross-sectional area. The jet-receiving opening ofthe evacuation lumen is locatable opposite the jet opening at apredetermined distance therefrom to receive a liquid jet when theinstrument is in operation. The nozzle is shaped to form a liquid jet asa liquid at high pressure flows therethrough. The liquid jet creates anentrainment region of moving liquid such that essentially all of themoving liquid in the entrainment region is directed into thejet-receiving opening when the instrument is in operation. In addition,the cross-sectional area of the jet-receiving opening and thepredetermined distance between the jet opening and the jet-receivingopening are selected so that the entrainment region occupies between 50%and 100% of the cross-sectional area of the jet-receiving opening whenthe instrument is in operation.

[0016] Another device comprises a surgical instrument that has a distalend adapted to perform a surgical procedure on a patient and a proximalend including a body. The body includes a grasping region that is shapedand positionable to be held by the hand of an operator. The instrumentincludes a pressure lumen that has sufficient burst strength to conducta high pressure liquid towards the distal end of the instrument andincludes at least one nozzle providing a jet opening. The instrumentfurther includes an evacuation lumen, supported by the body, thatincludes a jet-receiving opening locatable opposite the jet opening at apredetermined distance therefrom to receive a liquid jet when theinstrument is in operation. The distal end of the surgical instrumenthas a predetermined contour and size that is selected to facilitateinsertion of the distal end of the surgical instrument into a confinedregion of a body defining a surgical operating space for a specificsurgical procedure.

[0017] Yet another device comprises a surgical instrument that has adistal end adapted to perform a surgical procedure on a patient and aproximal end including a body. The instrument includes a pressure lumenthat has a sufficient burst strength to conduct a high pressure liquidtowards the distal end of the instrument, and that includes at least onenozzle providing a jet opening. The surgical instrument is constructedand arranged to be entirely disposable after a single use.

[0018] Another device comprises a surgical instrument that has a distalend adapted to perform a surgical procedure on a patient and a proximalend including a body. The body has a grasping region that is shaped andpositionable to be held by the hand of an operator. The instrumentincludes a pressure lumen having a sufficient burst strength to conducta high pressure liquid towards the distal end of the instrument. Thepressure lumen includes at least one nozzle providing a jet opening. Theinstrument further includes an evacuation lumen having a jet-receivingopening locatable opposite the jet opening at a predetermined distancetherefrom to receive a liquid jet when the instrument is in operation.At least one nozzle included in the instrument comprises a hole in theside wall of a lumen.

[0019] Yet another device comprises a surgical instrument having adistal end that is adapted to perform a surgical procedure on a patientand a proximal end that is adapted to be controllable by an operator.The instrument includes a pressure lumen that has a sufficient burststrength to conduct a high pressure liquid towards the distal end of theinstrument, and that includes at least one nozzle providing a jetopening. The instrument further includes an evacuation lumen including ajet-receiving opening locatable opposite the jet opening at apredetermined distance therefrom to receive a liquid jet when theinstrument is in operation. The nozzle is shaped to form a liquid jet asa liquid at high pressure flows therethrough, and the liquid jet isdirected into the jet-receiving opening when the instrument is inoperation. The evacuation lumen includes a region that is within and/ordownstream of the jet-receiving opening. The evacuation lumen is shapedand positionable so that a liquid within the region is able to macerateat least a portion of a tissue entrained in the liquid into a pluralityof particles when the instrument is in operation.

[0020] Another device comprises a surgical instrument that has a distalend that is adapted to perform a surgical procedure on a patient and aproximal end that includes a body. The body has a grasping region thatis shaped and positionable to be held by the hand of an operator. Theinstrument includes a pressure lumen that has a sufficient burststrength to conduct a high pressure liquid towards the distal end of theinstrument, and that includes at least one nozzle providing a jetopening. The instrument further includes an evacuation lumen that issupported by the body and that includes a jet-receiving openinglocatable opposite the jet opening to receive a liquid jet when theinstrument is in operation. At least a portion of the pressure lumenand/or evacuation lumen is rotatably moveable relative to the other foradjusting the separation distance between the jet opening and thejet-receiving opening.

[0021] Yet another device comprises a surgical instrument that has adistal end adapted to perform a surgical procedure on a patient and aproximal end that includes a body. The body has a grasping region thatis shaped and positionable to be held by the hand of an operator. Theinstrument includes a pressure lumen that has a sufficient burststrength to conduct a high pressure liquid towards the distal end of theinstrument, and that has a distal end including at least one nozzleproviding a jet opening. The instrument further includes an evacuationlumen supported by the body that includes a jet-receiving opening, whichis locatable opposite the jet opening to receive a liquid jet when theinstrument is in operation. The distal end of the pressure lumen isshaped to enable the jet opening to be positionable adjacent to asurface to be ablated or debrided such that a liquid jet emanating fromthe jet opening is separated from the surface by a distance essentiallyequal to a wall thickness, at the jet opening, of tubing comprising thepressure lumen.

[0022] Another device comprises a surgical instrument that has a distalend adapted to perform a surgical procedure on a patient and a proximalend that includes a body. The body includes a grasping region that isshaped and positionable to be held by the hand of an operator. Theinstrument includes a pressure lumen that has a sufficient burststrength to conduct a high pressure liquid towards the distal end of theinstrument, and that includes at least one nozzle providing a jetopening. The instrument further includes an evacuation lumen that has aproximal end and a distal end. The distal end of the evacuation lumenincludes a jet-receiving opening that is locatable opposite the jetopening at a predetermined distance therefrom to receive the liquid jetwhen the instrument is in operation. The evacuation lumen is shaped andpositionable to enable evacuation of essentially all of the liquidcomprising the liquid jet from the jet-receiving opening to the proximalend of the evacuation lumen without the need of an external source ofsuction.

[0023] Yet another device comprises a surgical instrument that has adistal end that is adapted to perform a surgical procedure on a patientand a proximal end that includes a body. The body includes graspingregion that is shaped and positionable to be held by the hand of anoperator. The body includes at least two actuating elements, where eachof the at least two actuating elements is adapted to be actuatable by asingle hand of an operator holding the grasping region. Each actuatingelement causes an essentially identical predetermined change in afunction, shape, position, or orientation of at least a portion of thedistal end of the instrument upon actuation of the element.

[0024] Yet another device comprises a surgical instrument that has adistal end that is adapted to perform a surgical procedure in a patientand a proximal end that includes a body. The body includes a graspingregion that is shaped and positionable to be held by the hand of anoperator. The body includes at least one actuating element that isadapted to be actuatable by a single hand of an operator holding thegrasping region. The actuating element is shaped and positionable on thebody to enable the operator to hold the body in one of at least twohand/grasping region orientations with a single hand and to effect anessentially identical predetermined change in a function, shape,position, or orientation of at least a portion of the distal end of theinstrument, upon actuation of the element, when holding the body ineither of the at least two hand/grasping region orientations.

[0025] Yet another device comprises a surgical instrument that has adistal end to perform a surgical procedure on a patient and a proximalend adapted to be controllable by an operator. The instrument includes apressure lumen that has a sufficient burst strength to conduct a highpressure liquid towards the distal end of the instrument, and thatincludes at least one nozzle providing a jet opening. The instrumentfurther includes an evacuation lumen that has a proximal end and adistal end and a jet-receiving opening near its distal end that islocatable opposite the jet opening to receive a liquid jet when theinstrument is in operation. The evacuation lumen has an internalcross-sectional area which increases essentially continuously from aminimum value at the jet-receiving opening to a maximum value at apredetermined position proximal of the jet-receiving opening. Thismaximum value is essentially constant at positions proximal to thepredetermined position.

[0026] Another device comprises a surgical instrument that has a distalend that is adapted to perform a surgical procedure on a patient and aproximal end that is adapted to be controllable by an operator. Theinstrument includes a pressure lumen comprising a tubular conduit havinga distal end and a proximal end. The pressure lumen has a sufficientburst strength to conduct a high pressure liquid towards the distal endof the instrument. The distal end of the tubular conduit has a neckedregion with a reduced cross-sectional dimension that is less than across-sectional dimension of the tubular conduit outside of and proximalto the necked region. The necked region comprises a nozzle that includesa jet opening and is shaped to enable the jet opening to form a liquidjet when a high pressure liquid flows therethrough. The nozzle isoriented so that at least a central region of the liquid jet is directedessentially perpendicular to a longitudinal axis of the conduit outsidethe necked region. The nozzle is also shaped so that essentially noportion of the jet opening projects radially beyond a perimeter definedby an outer surface of the tubular conduit in a region adjacent to thenozzle but outside the necked region.

[0027] In other embodiments, the invention provides devices specificallyfor use in a gaseous environment. In one such embodiment, the inventionprovides a device for use in a gaseous environment comprising a surgicalinstrument that has a distal end adapted to perform a surgical procedureon a patient and a proximal end that is adapted to be controllable by anoperator. The instrument includes a pressure lumen having a sufficientburst strength to conduct a high pressure liquid towards the distal endof the instrument, and that includes at least one nozzle providing a jetopening. The instrument further includes an evacuation lumen that has ajet-receiving opening that is locatable opposite the jet opening at apredetermined distance therefrom to receive a liquid jet when theinstrument is in operation. The nozzle is shaped to form a liquid jet asa high pressure liquid flows therethrough. The liquid jet comprises adiverging region of liquid droplets moving through the gaseousenvironment, with the diverging region having an apex located at the jetopening, such that essentially all of the moving liquid droplets in thediverging region are directed into the jet-receiving opening when theinstrument is in operation.

[0028] Another device for use in a gaseous environment comprises asurgical instrument that has a distal end that is adapted to perform asurgical procedure on a patient and a proximal end that is adapted to becontrollable by an operator. The instrument includes a pressure lumenthat has a sufficient burst strength to conduct a high pressure liquidtowards the distal end of the instrument, and that includes at least onenozzle providing a jet opening. The instrument further includes anevacuation lumen that has a proximal end and a distal end. The distalend of the evacuation lumen includes a jet-receiving opening that islocatable opposite the jet opening at a predetermined distance therefromto receive the liquid jet when the instrument is in operation. Theevacuation lumen is shaped and positionable to enable evacuation ofessentially all of the liquid comprising the liquid jet from thejet-receiving opening to the proximal end of the evacuation lumenwithout the need for an external source of suction.

[0029] Yet another device for use in a gaseous environment comprises asurgical instrument that has a distal end that is adapted to perform asurgical procedure on a patient and a proximal end adapted to becontrollable by an operator. The instrument includes a pressure lumenthat has a sufficient burst strength to conduct a high pressure liquidtowards the distal end of the instrument, and that has a distal endincluding at least two nozzles, where each nozzle provides a jetopening. Each nozzle is shaped to form a liquid jet as a liquid at highpressure flows therethrough. The instrument further includes anevacuation lumen that has a distal end including a jet-receiving openingthat is locatable opposite at least one of the jet openings at apredetermined distance therefrom. The predetermined distance between theat least one jet opening and the jet-receiving opening defines agas-filled gap between the jet opening and the jet-receiving opening.The jet-receiving opening is shaped and positionable to receive at leastone liquid jet when the instrument is in operation.

[0030] Yet another device for use in a gaseous environment comprises asurgical instrument that has a distal end that is adapted to perform asurgical procedure on a patient and a proximal end that is adapted to becontrollable by an operator. The instrument includes a pressure lumenthat has a sufficient burst strength to conduct a high pressure liquidtowards the distal end of the instrument, and that includes at least onenozzle providing a jet opening. The instrument further includes anevacuation lumen that has a jet-receiving opening locatable opposite thejet opening at a predetermined distance therefrom to receive a liquidjet when the instrument is in operation. The nozzle is shaped to form aliquid jet as a liquid at high pressure flows therethrough, and theliquid jet is directed across a gas-filled gap and into thejet-receiving opening when the instrument is in operation. The nozzleand the jet-receiving opening are shaped and positionable relative toeach other so that back-flow of a liquid mist or spray from thejet-receiving opening into the gas-filled gap is essentially eliminatedwhen the instrument is in operation.

[0031] Another device for use in a gaseous environment comprises asurgical instrument that has a distal end that is adapted to perform asurgical procedure on a patient and a proximal end that is adapted to becontrollable by an operator. The instrument includes a pressure lumenthat has a sufficient burst strength to conduct a high pressure liquidtowards the distal end of the instrument, and that includes at least onenozzle providing a jet opening. The instrument further includes anevacuation lumen including a jet-receiving opening that is locatableopposite the jet opening at a predetermined distance therefrom toreceive a liquid jet when the instrument is in operation. The nozzle isshaped to form a liquid jet as a high pressure liquid flowstherethrough. The liquid jet is directed across a gas-filled gap andinto the jet-receiving opening when the instrument is in operation. Thenozzle and the jet-receiving opening are shaped and positionablerelative to each other so that a cross-sectional shape and area of theliquid jet at a given location within the evacuation lumen isessentially the same as an internal cross-sectional shape and area ofthe evacuation lumen at the same given location. The given locationcomprises the jet-receiving opening and/or a location proximal to thejet-receiving opening.

[0032] In yet another aspect, the invention provides methods forutilizing a surgical liquid-jet instrument. In one embodiment, theinvention provides a method comprising inserting a surgical liquid-jetinstrument into a joint capsule of a patient, creating a liquid jet withthe surgical liquid-jet instrument, directing the liquid jet towards ajet-receiving opening in an evacuation lumen of the surgical liquid-jetinstrument, and cutting or ablating a selected tissue within the jointcapsule with the liquid jet.

[0033] In another embodiment, the invention provides a method comprisingpositioning a surgical liquid-jet instrument in close proximity to asurface of a body of patient, creating a liquid jet in a surroundinggaseous environment with the liquid-jet instrument, directing the liquidjet essentially tangential to the surface and towards a jet-receivingopening in an evacuation lumen, debriding a material from the surfacewith the liquid jet, and evacuating a liquid comprising the liquid jetand the debrided material from the jet-receiving opening to a proximalend of the evacuation lumen without the need for an external source ofsuction.

[0034] In yet another aspect, the invention provides a method forforming a jet nozzle region in a tube. The method comprises necking downan end of a tube providing a lumen to form a jet nozzle region in thetube that has a reduced cross-sectional dimension. The method furthercomprises offsetting the jet nozzle region from being essentiallyco-linear with an axial center line of the tube outside the jet nozzleregion to a position where an axial center line of the jet nozzle regionis displaced from the axial center line of the tube outside the jetnozzle region by a distance of about d=R−r, where R is the internalradius of the tube outside the jet nozzle region and r is the internalradius of the jet nozzle region.

[0035] Other advantages, novel features, and objects of the inventionwill become apparent from the following detailed description of theinvention when considered in conjunction with the accompanying drawings,which are schematic and which are not intended to be drawn to scale. Inthe figures, each identical or nearly identical component that isillustrated in various figures is represented by a single numeral. Forpurposes of clarity, not every component is labeled in every figure, noris every component of each embodiment of the invention shown whereillustration is not necessary to allow those of ordinary skill in theart to understand the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0036]FIG. 1 is a schematic illustration of a surgical liquid jetsystem;

[0037]FIG. 2a is a partially-cutaway schematic illustration of asurgical liquid jet instrument;

[0038]FIG. 2b is a partially-cutaway schematic illustration of a portionof a surgical liquid jet instrument, the portion including the distalend of the surgical liquid jet instrument;

[0039]FIG. 3a is a schematic illustration of a portion of a pressurelumen of a surgical liquid jet instrument;

[0040]FIG. 3b is a schematic illustration of a portion of pressure lumenof a surgical liquid jet instrument;

[0041]FIG. 3c is a partially-cutaway schematic illustration of a portionof a pressure lumen of a surgical jet instrument;

[0042]FIG. 3d is a partially-cutaway schematic illustration of a portionof a pressure lumen of a surgical liquid jet instrument;

[0043]FIG. 3e is a schematic illustration of a variety of liquid jetnozzles having various length to minimum diameter ratios;

[0044]FIG. 4 is a series of schematic illustrations illustrating amethod for forming a liquid jet nozzle region;

[0045]FIG. 5a is a partially-cutaway schematic illustration of a portionof the distal end of a surgical liquid jet instrument for use in asurrounding liquid environment;

[0046]FIG. 5b is a partially-cutaway schematic illustration of a portionof the distal end of surgical liquid jet instrument for use in asurrounding liquid environment, where the evacuation lumen includes aconstriction;

[0047]FIG. 5c is a schematic illustration of a portion of the distal endof a surgical liquid jet instrument, illustrating various geometricrelationships;

[0048]FIG. 6a is a partially-cutaway schematic illustration of a portionof the distal end of a surgical liquid jet instrument for use in asurrounding gaseous environment;

[0049]FIG. 6b is a partially-cutaway schematic illustration of a portionof the distal end of a surgical liquid jet instrument for use in asurrounding gaseous environment, where the evacuation lumen includes aconstriction;

[0050]FIG. 7a is a partially-cutaway schematic illustration of a portionof a surgical liquid jet instrument, the portion including the distalend of the surgical liquid jet instrument;

[0051]FIG. 7b is a partially-cutaway schematic illustration of a portionof a surgical liquid jet instrument, the portion including the distalend of the surgical liquid jet instrument;

[0052]FIG. 7c is a partially-cutaway schematic illustration of a portionof a surgical liquid jet instrument, the portion including the distalend of the surgical liquid jet instrument;

[0053]FIG. 7d is a partially-cutaway schematic illustration of a portionof a surgical liquid jet instrument, the portion including the distalend of the surgical liquid jet instrument;

[0054]FIG. 7e is a partially-cutaway schematic illustration of a portionof a surgical liquid jet instrument, the portion including the distalend of the surgical liquid jet instrument;

[0055]FIG. 8a is a schematic illustration of a rotatably deployablesurgical liquid jet instrument, where the instrument is in theundeployed configuration;

[0056]FIG. 8b is a schematic illustration of the surgical liquid jetinstrument as in FIG. 8a, shown in the deployed configuration;

[0057]FIG. 8c is a cross-sectional illustration of the surgical liquidjet instrument as in FIG. 8b;

[0058]FIG. 8d is a cross-sectional illustration of the sheath, pressurelumen, and evacuation lumen of the surgical instrument as in FIG. 8c;

[0059]FIG. 9 is a cross-sectional illustration of a deployable surgicalliquid jet instrument, where deployment of the instrument isaccomplished by longitudinal movement of the pressure lumen;

[0060]FIG. 10 is a cross-sectional illustration of a deployable surgicalliquid jet instrument, where deployment of the instrument isaccomplished by longitudinal movement of the evacuation lumen;

[0061]FIG. 11a is a schematic illustration of a rotatably deployablesurgical liquid jet instrument having a single actuating element;

[0062]FIG. 11b is a schematic illustration of a portion of the surgicalliquid jet instrument as in FIG. 11a showing more clearly the rotatablymounted component, sheath, and distal end of the instrument, when in theundeployed configuration;

[0063]FIG. 11c is a schematic illustration of a portion of the surgicalliquid jet instrument as in FIG. 11a showing more clearly the rotatablymounted component, sheath, and distal end of the instrument, when in thedeployed configuration;

[0064]FIG. 11d is a partially-cutaway schematic illustration of aportion of the surgical liquid jet instrument as in FIG. 11a:

[0065]FIG. 11e is a partially-cutaway schematic illustration of aportion of the surgical liquid jet instrument as in FIG. 11a:

[0066]FIG. 11f is a schematic illustration of the actuating element ofthe surgical liquid jet instrument as in FIG. 11a:

[0067]FIG. 12a is a schematic illustration of a portion of a rotatablydeployable surgical liquid jet instrument having two actuating elements;

[0068]FIG. 12b is a cross-sectional illustration of the surgical liquidjet instrument as in FIG. 12a;

[0069]FIG. 12c is a cross-sectional illustration of the surgical liquidjet instrument as in FIG. 12a ;

[0070]FIG. 12d is a cross-sectional illustration of the surgical liquidjet instrument as in FIG. 12a ;

[0071]FIG. 12e is a cross-sectional illustration of the surgical liquidjet instrument as in FIG. 12a ;

[0072]FIG. 13 is an exploded, perspective illustration of a portion of arotatably deployable surgical liquid jet instrument having two actuatingelements;

[0073]FIG. 14a is a schematic illustration of the surgical liquid jetinstrument having a pressure lumen that includes two nozzles, eachproviding a jet opening;

[0074]FIG. 14b is a partially-cutaway schematic illustration of thesurgical liquid jet instrument as in FIG. 14a.

DETAILED DESCRIPTION

[0075] The present invention provides a variety of liquid jetinstruments useful in a variety of applications, many of which areespecially well suited for a variety of surgical procedures. The liquidjet instruments provided by the invention can be configured in a varietyof different ways for use in various surgical operating fields.Preferred surgical instruments, according to the invention, areconfigured as surgical handpieces having a proximal end with a graspingregion, or handle, shaped and configured to be comfortably held in thehand of an operator. The instruments also have a distal end thatincludes at least one nozzle for forming a liquid jet. The distal end ofthe inventive surgical instruments is utilized to perform a surgicalprocedure on a patient. Although the liquid jet instruments describedherein are shown as having a handpiece configuration, it should beunderstood that the invention is not strictly limited to surgicalhandpieces, and that the invention may also be practiced utilizingliquid jet instruments having a variety of configurations and purposes.For example, instead of being configured as a surgical handpiece, theinventive liquid jet instrument could alternatively be configured as anelongated catheter for use in the vasculature of a patient, for examplein thrombectomy procedures. In other embodiments, the inventive liquidjet instruments could be configured for manipulation by machine control,such as an X/Y/Z positioning machine. Also, the liquid jet instrumentsprovided by the invention can be used in a wide variety of surgicalapplications to utilize a high pressure liquid stream to cut, drill,bore, perforate, strip, delaminate, liquefy, ablate, shape, or formvarious tissues, organs, etc. of the body of a patient.

[0076] The liquid jet surgical instruments provided by the inventioninclude a pressure lumen, having a distal end terminating in at leastone nozzle providing a liquid jet opening, and having a proximal endthat is connectable to a source of liquid under high pressure, supplied,for example, by a high pressure pump or liquid dispenser. The liquid jetnozzle is shaped to form a liquid jet as a liquid under high pressureflows through the nozzle, as described below. The liquid jet, inpreferred embodiments, can be used to cut, ablate, sculpt, trim, form,debride, etc., various tissues of a patient in surgical procedures. Inpreferred embodiments, the liquid pressure supplied to the instrument bythe pump or dispenser is variably controllable by an operator of theinstrument so that the cutting or ablating power of the liquid jet isadjustable by the operator. This adjustability of the pressure can allowan operator to create a liquid jet with the instrument that candifferentiate between different types of tissue within a surgicaloperating field. For example, a lower pressure can be utilized forcutting or ablating a soft tissue such as fat from a surface of a hardertissue, such as muscle or bone, where the liquid jet has sufficientstrength to cut or ablate the soft tissue without damaging theunderlying harder tissue. A higher pressure can then be selected that issufficient to form a liquid jet capable of cutting or ablating hardtissue, such as muscle or bone. In this way, a liquid jet surgicalinstrument provided by the invention can provide highly selective andcontrollable tissue cutting in various surgical procedures.

[0077] Preferred embodiments of the inventive surgical instruments alsoinclude a liquid jet target or deflector, which is locatable oppositethe orifice in the nozzle from which the liquid jet is emitted(hereinafter referred to as the “liquid jet opening” or “jet opening”)at a predetermined distance from the liquid jet opening in order toreceive and/or deflect a liquid jet when the instrument is in operation.Embodiments including a target or deflector are preferred because thetarget/deflector prevents the liquid jet from being misdirected duringuse and potentially causing damage to unintended tissue sites in thesurgical operating field. The target/deflector enables the instrument toprovide a predetermined liquid jet length, defined by the predetermineddistance between the liquid jet opening in the nozzle and the surface ofthe target/deflector upon which the liquid jet impinges. With suchembodiments, the liquid jet can be utilized for performing surgicalcutting or ablating of tissue without the danger of causing untendedcollateral damage to tissue lying beyond the target/deflector in thesurgical operating field.

[0078] In some embodiments, the target/deflector can be simply a solidsurface capable of deflecting and transforming the liquid jet into aharmless spray. In preferred embodiments, however, the target is definedby a jet-receiving opening included in an evacuation lumen that formspart of the surgical instrument. In the preferred embodiments includingan evacuation lumen having a jet-receiving opening, in addition toproviding a defined liquid jet length (defined by the predetermineddistance between the liquid jet opening and the jet-receiving opening)and preventing unintended damage to surrounding tissue as discussedabove, the evacuation lumen can also be utilized for removing liquid,ablated tissue, and debris from the surgical field with the instrument.

[0079] In some embodiments, an external source of suction, for example avacuum pump or aspirator, can be provided in fluid communication with aproximal end of the evacuation lumen in order to provide the suctiondriving force required for evacuating material from the surgical fieldvia the jet-receiving opening. In preferred embodiments, however, theinvention provides surgical instruments having an evacuation lumen thatis shaped and positionable relative to the jet nozzle (as will becomeapparent to those of ordinary skill in the art from the detaileddescription below) to enable evacuation of essentially all of the liquidcomprising the liquid jet as well as ablated tissue and debris from thesurgical site without requiring an external source of suction. Inpreferred embodiments, the evacuating force created by the liquid jetbeing directed into the evacuation lumen is sufficient to evacuatematerial from the operating site to a drainage reservoir located at theproximal end of the evacuation lumen or an evacuation conduit connectedto the proximal end of the evacuation lumen. In such embodiments, theliquid jet and the evacuation lumen together act as an eductor pump,which utilizes the momentum and kinetic energy of the moving fluid ofthe liquid jet to create an evacuating force capable of driving theliquid, ablated material, and debris through the evacuation lumen andaway from the surgical site.

[0080] As discussed in detail below, the invention teaches thateffective evacuation of material through the evacuation lumen withoutthe use of an external source of suction (i.e., via eductor pump action)requires the design of the inventive instruments to provide certaingeometrical relationships between components relating, for example, thesize of the jet-receiving opening in the evacuation lumen to thepredetermined distance between the jet-receiving opening and the jetopening in the nozzle. Also, as taught by the invention, interrelatedwith the above-mentioned geometrical relationships in providingeffective eductor-pump action is the design of the liquid jet nozzle,shape of the jet-receiving opening and distal end of the evacuationlumen, the angular orientation of the liquid jet with respect to theevacuation lumen, as well as the surrounding medium in which thesurgical instrument is utilized. The present invention provides, in someembodiments, surgical instruments designed to account for some or all ofthe above-mentioned parameters to provide efficient evacuation, withoutthe need for an external source of suction, for instruments having awide variety of configurations and intended uses.

[0081] In one set of embodiments, the invention provides surgical liquidjet instruments constructed and arranged for use in a liquid surgicalenvironment, where the liquid jet opening and the jet-receiving openingare both submerged in a liquid when the instrument is in operation. Themeaning of “constructed and arranged for use in a liquid environment” asused herein refers to an inventive combination of structural featuresand geometric relationships between such features, which arespecifically selected to provide improved performance of the instrumentsin a liquid environment, as will become readily apparent to those ofordinary skill in the art upon reading the detailed description below.Such devices can be configured as surgical handpieces for use, forexample, in endoscopic, arthroscopic, or open surgery. As previouslymentioned, such devices could also be configured as catheters for use inthe vasculature of a patient.

[0082] Another class of surgical instruments provided by the inventionare constructed and arranged for operation in a gaseous environment,such as in air, where the distal end of the instrument, including thefluid jet nozzle and jet-receiving opening, are essentially completelysurrounded by gas when the instruments are in operation. The meaning of“constructed and arranged for operation in a gaseous environment” asused herein refers to an inventive combination of structural featuresand geometric relationships between such features, which arespecifically selected to provide improved performance of the instrumentsin a gaseous environment, as will become readily apparent to those ofordinary skill in the art upon reading the detailed description below.Typical surgical procedures contemplated for using surgical instrumentsprovided by the invention in gaseous environments involve proceduresperformed in a surrounding air environment, including, for example,surgical procedures on an external surface of a patient or certain openand minimally invasive surgical procedures. However, the surgicalinstruments designed for use in a gaseous environment provided by theinvention are not limited for use in air but could be used whensurrounded by any other gas, for example nitrogen, oxygen, carbondioxide, mixtures thereof, etc.

[0083] The surgical liquid jet instruments designed for use in a gaseousenvironment that are provided by the invention can be advantageouslyutilized for a number of surgical procedures including certain opensurgeries, laparoscopic surgeries, oral surgeries, and others. Onepreferred application of the inventive surgical liquid jet instrumentsfor use in an air environment involves the use of such instruments on anexternal surface of the body of a patient for debriding wounds, burns,sites of infection, and other breaches of the human skin. The term“debriding” when used in this context refers to removal of a materialfrom a surface via the liquid jet instrument. The material removed fromthe surface can, for example, comprise living tissue, dead tissue,foreign matter or debris embedded in the surface, infective material,etc. As will be discussed in greater detail below, preferred geometricrelationships and design parameters, for providing efficient operation,for different components of the inventive surgical instruments differfor surgical instruments designed for use when submerged in a liquid andsurgical instruments designed for use in a surrounding gaseousenvironment.

[0084] The inventive surgical liquid jet instruments, in preferredembodiments, can be configured to effectively remove material from asurgical site and transport the material through the evacuation lumenwithout the need for an external source of suction, for a wide varietyof angular orientations between the central region of the liquid jet andthe longitudinal axis of the evacuation lumen. The term “central regionof the liquid jet” as used herein refers to a region defining thegeometric center of the liquid jet. This region is typically anessentially cylindrical region of the liquid jet confined within acylinder whose outer surface has a shape and perimeter defined by theinner circumference of the liquid jet opening, which circumference isprojected from the liquid jet opening to the jet-receiving opening alongan axis that is co-linear with the longitudinal axis of the jet nozzle.The “longitudinal axis” of the jet nozzle, as will be described in moredetail below, is defined by the axial center line of the nozzle regionof the pressure lumen. The “longitudinal axis” of the evacuation lumenrefers to an axis defining the geometric center of the evacuation lumenin a region that is proximal to the jet-receiving opening. In typicalembodiments, this region of the evacuation lumen will have alongitudinal axis that is essentially parallel to the longitudinal axisof the elongated body of the instrument, which is held and controlled bythe hand of the operator (or, for embodiments involving configurationsnot including a body, such as a catheter configuration, the proximal endof the surgical instrument, not inserted into the patient, which iscontrollable by the operator). As used herein in the context ofdescribing geometric relationships between longitudinal axes of variouscomponents, the term “co-linear” refers to components whose longitudinalaxes are superimposed on essentially the same line in space. The term“parallel” when used in the same context herein refers to longitudinalaxes that are not co-linear, but that are oriented in an essentiallyidentical direction in space. Accordingly, the surgical instrumentsprovided by the invention enable effective evacuation of material anddebris from the surgical site, without the need for an external sourceof vacuum, for a wide variety of liquid jet angular configurations,including instruments providing liquid jets that are directed axially,transversely, or at any angle between 0 and 180° with respect to alongitudinal axis defining the proximal end, or body, of the surgicalinstrument. Such flexibility allows the inventive surgical instrumentsto be designed having a distal end that has a variety of predeterminedcontours, shapes, and sizes specifically selected for particularsurgical procedures. Such customization of the instruments allows theliquid jet instruments to be designed and configured to facilitate andreduce the difficulty of insertion of the distal end of the device intoconfined regions of the body defining a surgical operating space. Forexample, as will be discussed in greater detail below, the inventionprovides surgical liquid jet instruments and a surgical method forperforming arthroscopic surgical procedures, or other surgicalprocedures, in joint capsules of a patient, for example in the knee.

[0085] To further facilitate insertion of the inventive surgical liquidjet instruments into confined surgical operating spaces, in a number ofpreferred embodiments, especially involving instruments designed foroperation when submerged in a liquid environment, the invention providessurgical instruments having deployable distal ends. The term“deployable” as used herein refers to a surgical liquid jet instrumenthaving a distal end where either the pressure lumen, the evacuationlumen, or both are moveable relative to each other in order to vary thepredetermined distance between the liquid jet opening in the nozzle andthe jet-receiving opening in the evacuation lumen. Typically, suchinstruments are inserted into the operating site in an undeployedconfiguration, where in the undeployed configuration the predetermineddistance mentioned above is small or essentially zero and the distal endof the instrument has a minimum cross-sectional dimension for insertion.After insertion, the operator can, by manipulating the proximal end orbody of the instrument, deploy the distal end to provide the desiredpredetermined distance between the jet opening and the jet-receivingopening and, thus, the desired liquid jet length. As described in moredetail below, the deployment can involve, for example, a longitudinalmovement of one or both of the lumen with respect to the proximal end orbody of the instrument, a lateral movement of one or both of the lumen,a rotational movement of one or both of the lumen, or a combination ofany of the above, so long as the movement involves a change in thepredetermined distance between the liquid jet opening and thejet-receiving opening.

[0086] As will be described in more detail below, in some preferredembodiments, the proximal end of the instrument comprises a body with agrasping region for an operator. The body can include at least oneactuating element that can be manipulated by an operator to cause apre-determined change in a function, shape, position, or orientation ofat least a portion of the distal end of the instrument upon actuation.For example, the actuating element(s) can be used to deploy the distalend of the instrument. For embodiments including two or more actuatingelements according to the invention, the actuating elements preferablycause an essentially identical predetermined change in a function,shape, position, or orientation of at least a portion of the distal endof the instrument upon actuation, as described in greater detail below.In some preferred embodiments, the actuating element(s) can bepositioned to be easily actuated by a single hand of an operator for atleast two different hand/grasping region orientations, thus permittingthe operator to hold the instrument in at least two distinct positionswithin her hand while still being able to actuate the actuatingelement(s).

[0087] The inventive liquid jet surgical instruments advantageouslyinclude distal ends that are designed and configured, for someembodiments, to prevent or reduce plugging of the evacuation lumen,blow-by of the liquid jet, or back spray or misting of the liquid jetwhen the instrument is in operation. “Blow-by” of the liquid jet, asused herein, refers to a portion of the liquid jet, or a high velocityfluid entrained by the liquid jet (comprising the “entrainment region”as discussed below), having a cross-sectional area, at the plane of thejet-receiving opening, that is larger than the cross-sectional area ofthe jet-receiving opening so that at least a portion of the liquid jetor high velocity fluid misses or “blows by” the jet-receiving opening.Blow-by is generally undesirable because it can lead to unintendedtissue damage and poor evacuation efficiency. “Back spray” as usedherein refers to a liquid jet, or high velocity fluid entrained by theliquid jet, entering the jet-receiving opening in the evacuation lumenand subsequently reflecting or flowing back into the surgical field fromthe jet-receiving opening. Such back spray is undesirable in operationdue to the potential of contamination of the surgical operating fieldand/or aerosolization of infective material, in addition, back spraytypically indicates a poor efficiency level of the evacuation ofmaterial by the instrument via eductor pump action. As described in moredetail below, the surgical instruments provided by the inventionsubstantially reduce, and in preferred embodiments essentiallyeliminate, performance problems associated with blow-by and back spraywhen the instruments are in operation.

[0088] Plugging of the evacuation lumen can be prevented, forembodiments involving surgical instruments designed for operation in aliquid environment, by constructing the evacuation lumen to have aregion that is within and/or downstream of the jet-receiving openingthat is designed to be able to macerate at least a portion of the tissueentrained by the liquid jet into a plurality of particles when theinstrument is in operation. The term “macerate” as used herein refers toa disaggregation of entrained material, for example an entrained tissue,by a liquid within the evacuation lumen undergoing intensely turbulentflow that creates a region of extremely high fluid shear and impactingforces capable of partitioning the material into particles having a sizesmall enough to pass through the evacuation lumen without plugging thelumen. In preferred embodiments, the evacuation lumen is able tomacerate a substantial fraction of the tissue entrained into a pluralityof essentially microscopic particles. “Microscopic” as used hereinrefers to particles having a dimension too small to be visualizedunaided by the human eye. Prevention of blow-by and back spray can beaccomplished by providing a surgical liquid jet instrument having adistal end configured so that when in operation, the liquid jet and thehigh velocity fluid entrained by the liquid jet occupies a substantialfraction of the cross-sectional area of the jet-receiving opening, butdoes not occupy a region larger than the cross-sectional area of thejet-receiving opening. As discussed in more detail below, this“substantial fraction” refers to at least 50%, but less than 100% of thecross-sectional area of the jet-receiving opening being occupied by anentrainment region created by the liquid jet.

[0089] The inventive surgical liquid jet instruments will now bedescribed in more complete detail in the context of several specificembodiments illustrated in the appended figures. It is to be understoodthat the embodiments described are for illustrative purposes only andthat the novel features of the invention, as described in the appendedclaims, can be practiced in other ways or utilized for instrumentshaving other configurations, as apparent to those of ordinary skill inthe art.

[0090]FIG. 1 shows one embodiment of a liquid jet surgical system 100utilizing a liquid jet surgical instrument 102, according to theinvention. The surgical instrument 102 illustrated is configured as asurgical handpiece having a proximal end 103 including a body 104 havinga grasping region 106 configured for placement in the hand of anoperator of the instrument. The surgical instrument 102 has a distal end108 including a pressure lumen 110 and an evacuation lumen 112. “Distalend” when used herein in the context of a region of a surgicalinstrument refers to the portion of the surgical instrument that isadapted to perform a surgical procedure on a patient, and which isinserted into a surgical site during operation of the instrument. Thedistal end of the instrument 108 can, in some embodiments, comprise onlythe distal ends of pressure lumen 110 and evacuation lumen 112, or inother embodiments, can include components proximal to the distal ends ofthe pressure lumen 110 and the evacuation lumen 112 that are alsoinserted into a surgical operating space of the patient during use ofthe instrument.

[0091] In the illustrated embodiment, surgical instrument 102 furtherincludes a sheath 114, which at least partially surrounds pressure lumen110 and evacuation lumen 112 and supplies support for the lumen toassists in maintaining and/or establishing a desired geometricconfiguration between pressure lumen 110 and evacuation lumen 112, whenthe instrument 102 is in operation. Pressure lumen 110 further includesat its distal end a nozzle 116, which forms a liquid jet as a highpressure liquid supplied by pressure lumen 110 streams therethrough.Evacuation lumen 112 includes a jet-receiving opening 118 located at itsdistal end and positioned, when the instrument 102 is in operation,opposite the jet nozzle 116 at a predetermined distance therefrom inorder to receive the liquid jet 120.

[0092] In the particular embodiment illustrated, liquid jet 120 isdirected transversely (e.g., at an angle of approximately 90°) withrespect to the longitudinal axes of the evacuation lumen 112 and thebody 104 of the instrument 102. As will be explained in more detailbelow, for such embodiments, the evacuation lumen 112 preferablyincludes a jet-deflecting portion 122 downstream and adjacent to thejet-receiving opening 118 that is utilized to deflect and direct theliquid entering the jet-receiving opening 118 proximally withinevacuation lumen 112. Pressure lumen 110 and evacuation lumen 112 arepreferably constructed from a surgical grade stainless steel, however,in alternative embodiments, either or both of the lumen may beconstructed from other suitable materials, for example certain polymericmaterials, as apparent to those of ordinary skill in the art. Regardlessof the specific material from which the pressure lumen is constructed,pressure lumen 110 must have sufficient burst strength to enable it toconduct a high pressure liquid to nozzle 116 in order to form liquid jet120. The burst strength of pressure lumen 110 should be selected to meetand preferably exceed the highest contemplated pressure of the liquidsupplied for use in the specific surgical procedure to be performed.Typically, surgical instrument 102 will operate at liquid pressurebetween about500 psig and about 50,000 psig, depending on the intendedmaterial to be cut and/or ablated. Those of ordinary skill in the artwill readily be able to select appropriate materials for formingpressure lumen 110 and evacuation lumen 112 for particular surgicalrequirements.

[0093] In preferred embodiments, pressure lumen 110 and evacuation lumen112 are constructed and supported so that the distal ends of the lumensare sufficiently stiff to prevent deflection of the lumens by, forexample, contact with surfaces within the surgical operating space,which deflection could potentially lead to misdirection of liquid jet120 so that it is no longer incident upon jet-receiving opening 118,thus potentially causing unintended tissue damage to the patient.Pressure lumen 110 is in fluid communication with high pressure pump 124via high pressure liquid supply conduit 126. High pressure liquid supplyconduit 126 must also have a burst strength capable of withstanding thehighest liquid pressures contemplated for using the instrument 102 for aparticular surgical application. In some embodiments, high pressureliquid supply conduit 126 comprises a burst-resistant stainless steelhypotube constructed to withstand at least 50,000 psig. In someembodiments, the hypotube may be helically coiled to improve theflexibility and maneuverability of the surgical instrument 102. Inpreferred embodiments, high pressure liquid supply conduit 126 comprisesa para-aramid (e.g. KEVLAR™) reinforced nylon tube that is connectableto the pressure lumen 110.

[0094] In fluid communication with high pressure liquid supply conduit126 is a high pressure pump 124, which can be any suitable pump capableof supplying the liquid pressures required for performing the desiredsurgical procedure. Those of ordinary skill in the art will readilyappreciate that many types of high pressure pumps may be utilized forthe present purpose, including, but not limited to, piston pumps anddiaphragm pumps. In preferred embodiments, high pressure pump 124comprises a disposable piston or diaphragm pump, which is coupled to areusable pump drive console 128. High pressure pump 124 has an inletthat is in fluid communication with a low pressure liquid supply line130, which receives liquid from liquid supply reservoir 132. Pump driveconsole 128 preferably includes an electric motor that can be utilizedto provide a driving force to high pressure pump 124 for supplying ahigh pressure liquid in liquid supply conduit 126.

[0095] While a variety of known pump consoles may be utilized in thecontext of the present invention, the preferred pump drive consoleincludes a constant speed electric motor that can be turned on and offby means of an operator-controlled switch 134. In preferred embodiments,operator-controlled switch 134 comprises a foot pedal or a button ortrigger located on grasping region 106 of the surgical instrument 102that may be easily accessed by the operator of the instrument. In someembodiments, pump drive console 128 can have a delivery pressure/flowrate that is factory preset and not adjustable in use. In otherembodiments, the pressure/flow rate may be controlled by the operatorvia an adjustable pressure/flow rate control component 136, that cancontrol the motor speed of the pump drive console and/or thedisplacement of the high pressure pump. While in FIG. 1, pressure/flowrate control component 136 is illustrated as a knob on pump driveconsole 128, in preferred embodiments, such component would preferablycomprise a foot pedal, or trigger/button located on grasping region 106,as previously discussed for on/off control of the pump drive console128. In yet other embodiments, pump drive console 128 and high pressurepump 124 may be replaced by a high pressure liquid dispenser or othermeans to deliver a high pressure liquid, as apparent to those ofordinary skill in the art.

[0096] The liquid utilized for forming the liquid cutting jet can be anyfluid that can be maintained in a liquid state at the pressures andtemperatures contemplated for performing the surgical procedures. Forapplications in which the instruments are used to perform surgicalprocedures in a live patient, the liquid utilized should also bephysiologically compatible. In typical embodiments, the liquid suppliedwill be a sterile surgical saline solution, or sterile water and liquidsupply reservoir 132 can comprise a sterile container, such as anintravenous (IV) bag containing such fluid. In some embodiments, inorder to improve the cutting or ablating character of the liquid jet,the liquid may contain solid abrasives, or the liquid may comprise aliquefied gas, for example carbon dioxide, which forms solid particulatematerial upon being admitted from nozzle 116 to for the liquid jet 120.In other embodiments, the liquid supplied to surgical instrument 102 mayinclude medicaments, such as antiseptics, antibiotics, antiviralcomponents, anesthetics, drugs, chemotherapy agents, etc., that areuseful in the context of a specific surgical procedure. In otherembodiments, the fluid may include a dye to improve visualization of theliquid jet when the instrument is in operation.

[0097] Evacuation lumen 112 is connectable at its proximal end to anevacuation conduit 138, which can be used to transport evacuatedmaterial and debris to a drainage reservoir 140. The liquid contained inevacuation conduit 138 is under relatively low pressure and,accordingly, evacuation conduit 138 may be constructed, in preferredembodiments, of a low cost flexible material, for example, polymerictubing, such as polyvinyl chloride (PVC), silicone, polyethylene,rubber, etc. tubing. In preferred embodiments, evacuation conduit 138should have a minimum internal cross-sectional area that equals orexceeds the maximum internal cross-sectional area of evacuation lumen112. In the illustrated embodiment, surgical instrument 102 isconstructed such that evacuation lumen 112 is capable of evacuatingliquid jet 120 and ablated material and debris from the jet-receivingopening 118 to the proximal end of evacuation lumen 112 and throughevacuation conduit 138 into drainage reservoir 140, without the need foran external source of suction. In such embodiments, it is preferred thatevacuation conduit 138 include a vacuum breaker 142 or a proximal endthat is not couplable to an external source of suction, so that it isnot possible for an operator to inadvertently couple evacuation conduit138 to an external source of suction when the instrument is inoperation.

[0098] In preferred embodiments, the fluid supply path of liquid jetsurgical system 100 is disposable, and sterilizable, for example bychemical methods such as exposure to ethylene oxide, or by gamma or betairradiation, as apparent to those of ordinary skill in the art. Inespecially preferred embodiments, the fluid path is suppliedpre-sterilized to the user for a single use only. Those of ordinaryskill in the art understand what is meant by “disposable” and “for asingle use only.” Disposability of the liquid supply path, includingliquid supply reservoir 132, liquid supply line 130, high pressure pump124, high pressure liquid supply conduit 126, and pressure lumen 110 isadvantageous because such components can be difficult to effectivelyclean and sterilize between use without reducing the utility of theinstrument, for example by the plugging of jet nozzle 116 with depositsduring the sterilization process. In especially preferred embodiments,all of the components of liquid jet surgical system 100 are entirelydisposable after a single use except for pump drive console 128. Forembodiments where the surgical liquid jet instrument is disposable aftera single use, the instrument is preferably sterilizable, and mostpreferably provided pre-sterilized. In other embodiments, only thepressure lumen and the distal end of the instrument for insertion intothe patient are sterilizable or pre-sterilized.

[0099] Grasping region 106 may be configured in a wide variety of shapesand configurations depending on the ergodynamics of a particularsurgical operating procedure and/or the preference of a particularoperator. For example, as opposed to the grasping region 106illustrated, which comprises an elongated handle, the grasping regionmay be formed in the shape of a pistol, or with loops, straps, rings,finger slots, etc., as apparent to those of ordinary skill in the art.

[0100] Surgical instrument 102 is shown in greater detail in FIG. 2a.Specifically, FIG. 2a shows partially cutaway views of body 104 ofsurgical instrument 102, sheath 114, pressure lumen 110 and evacuationlumen 112. Now more clearly visible is jet opening 144 located at theoutlet of nozzle 116, which jet opening 144 defines the apex of liquidjet 120 as it is emitted from nozzle 116. Also more clearly visible arethe jet-receiving opening 118 and jet-deflecting portion 122 ofevacuation lumen 112. In the illustrated embodiment, liquid jet 120 isdirected into jet-receiving opening 118 such that the axis 146 definingthe direction of the central region of liquid jet 120 is essentiallyperpendicular to the longitudinal axis of sheath 114 and the proximalend 103 of surgical instrument 102.

[0101] Sheath 114 can comprise a tube that is attached at its proximalend to the body 104 of surgical instrument 102 and which includes twochannels therewithin. Through one channel 115 traverses pressure lumen110 and through the other channel 117 traverses evacuation lumen 112.The channels 115, 117 through which the lumen 110, 112 traverse areseparated by a central spacer region 148. Sheath 114 may be constructedfrom a variety of known materials, as apparent to those of ordinaryskill in the art. In preferred embodiments, sheath 114 is constructed ofa surgical grade stainless steel. In alternative embodiments to thatshown, sheath 114 may comprise a simple tube without central region 148,and the pressure lumen and evacuation lumen may be disposed within thesheath, such that they are in direct contact with each other along thelength of the sheath. Such an embodiment is preferred for devices wherea minimal cross-sectional dimension of the distal end of the instrumentis desirable.

[0102] Pressure lumen 110 and/or evacuation lumen 112 may be rigidlyconnected to the sheath 114 in one or more locations along the length ofthe sheath, for embodiments where the lumen are immobile with respect tothe sheath. In alternative embodiments, to be discussed in more detailbelow, at least one of the lumen may be slidable and/or rotatable withinthe sheath. The lumen may be immobilized within sheath 114 via a varietyof methods, for example, by simple friction between the walls of thelumen and the inner surface of one or more portions of sheath 114, bywelding, gluing, press fitting, or other methods of affixing an outersurface of a lumen to an inner surface of the sheath, or by any othermethods apparent to those of ordinary skill in the art. In alternativeembodiments to that shown in FIG. 2a, sheath 114 may be eliminatedentirely. In such embodiments, the pressure lumen and evacuation lumenmay be directly connected to each other, for example, by welding,gluing, etc., or may be coupled to each other via straps, rings, clips,or other means apparent to those of ordinary skill in the art.

[0103] The cutaway region shown of body portion 104 of surgicalinstrument 102 shows the connection between pressure lumen 110 and highpressure liquid supply conduit 126, and the connection betweenevacuation lumen 112 and evacuation conduit 138, according to oneembodiment. Proximal end 150 of pressure lumen 110 is coupled to highpressure liquid supply conduit 126 via high pressure tubing coupler 152.High pressure tubing coupler 152 can comprise a stainless steel barbedfitting including, in some embodiments, a crimped sleeve disposed overthe barbed fitting to hold the ends of the pressure lumen 110 and highpressure liquid supply conduit 126 securely in place when underpressure. In alternative embodiments, the high pressure tubing couplercan be secured to the ends of the pressure lumen and the high pressureliquid supply conduit by means of an epoxy adhesive or other sealant asapparent to those of ordinary skill in the art. As opposed to theessentially permanent connections described immediately above, inalternative embodiments, the high pressure tubing coupler may comprise ahigh pressure detachable or uncouplable element, such as a variety ofhigh pressure tubing fittings known to those of ordinary skill in theart. Similarly, the proximal end 154 of evacuation lumen 112 can becoupled to evacuation conduit 138 via a low pressure tubing coupler 156.Low pressure tubing coupling element 156 can comprise any of a varietyof low pressure tubing fittings known in the art, including but notlimited to, barbed fittings, LEUR-LOCK™ fittings, etc. Preferably, lowpressure coupling element 156 has a minimum internal cross-sectionalarea that is at least as great as the maximum internal cross-sectionalarea of evacuation lumen 112. The pressure lumen 110, evacuation lumen112, high pressure liquid supply conduit 126, and evacuation conduit 138are supported and positioned within body 104 via support elements 157,which can comprise an extension or protrusion from an internal surfaceof body 104 having slots, grooves, or holes therein through which thelumen/conduits pass.

[0104]FIG. 2b shows an alternative embodiment of a sheath and distal endof a surgical instrument having a sheath 158 that is not straight asabove, but instead is curved at the distal end 160 of the instrument.Such a configuration may be advantageous for reducing the difficulty ofinsertion of the distal end 160 of the instrument in certain surgicalspaces. Sheath 158 provides an orientation of nozzle 116 andjet-receiving opening 143 such that the axis 146 defining the directionof the central region of liquid jet 120 emitted from jet opening isessentially parallel to the longitudinal axis of the proximal end ofsheath 158 and the proximal end of the instrument. In the illustratedembodiment the central region of liquid jet 120 is directed at an angleof about 180° with respect to a longitudinal axis of a proximal end ofthe instrument, to which sheath 158 is connected, and at an angle ofabout 90° with respect to the longitudinal axis 162 of evacuation lumen164 in a region proximal to the curved, jet-deflecting portion 122 ofevacuation lumen 164.

[0105]FIGS. 3a-3 d show a variety of embodiments for the distal regionof the pressure lumen providing the liquid jet nozzle and jet opening.FIG. 3a shows the distal region of one embodiment of a pressure lumen,which is preferred for use in surgical instruments that are designed tobe utilized in a liquid environment. Pressure lumen 170 comprises atubular conduit having a necked region 172 of the conduit definingnozzle 174, which necked region has an internal cross-sectional areathat is less than an internal cross-sectional area of the tubularconduit outside of and proximal to necked region 172. The distal end ofpressure lumen 170 is further configured to enable jet opening 176 to bepositioned adjacent to a surface 178 to be ablated or debrided by thesurgical instrument, such that a liquid jet emanating from jet opening176 is separated from surface 178 by a distance that is essentiallyequal to a wall thickness of the tubing comprising nozzle 174 at theregion of jet opening 176. Nozzle 174 can be formed in pressure lumen170 by methods described below, and enables an operator of the surgicalinstrument including pressure lumen 170 to position nozzle 174 adjacent,or in close proximity to, a surface 178 to be ablated or debrided and todirect a liquid jet essentially parallel to surface 178 at a very smalldistance therefrom. Nozzle region 174 is bent with respect to the axialcenter line 180 of pressure lumen 170 outside jet nozzle region 174 sothat jet opening 176 emits a liquid jet whose central region is directedalong an axis 182 that forms an angle θ with respect to axis 180. Angleθ can be any angle between about 0 and about 90 degrees and, inpreferred embodiments, is an angle of about 90 degrees.

[0106] The nozzle shown in FIG. 3a also advantageously provides atransversely-directed liquid jet and a relatively large nozzle length tointernal diameter ratio, while simultaneously providing a small profilefor pressure lumen 170 due to the fact that the nozzle 174 does notproject radially beyond a parameter defined by the outer surface of thetubular conduit forming the pressure lumen 170 in the region 173 that isadjacent and proximal to necked region 172. Nozzle 174, when utilizedfor surgical instruments for use in a liquid environment, preferably hasa region having a minimum internal diameter, where the region has alength that exceeds its minimal internal diameter by at least a factorof about four, more preferably by at least a factor of about six. Inother embodiments, the region has a length that exceeds its minimalinternal diameter by at least a factor of about ten. As will bediscussed in more detail below, the greater the ratio of the length tominimum internal diameter of the nozzle region, the more narrowlyfocused and collimated is the liquid jet that is emitted from jetopening 176. For reasons described in more detail below, highlycollimated liquid jets are generally preferred for embodiments involvingsurgical instruments for use in liquid environments; however, ingeneral, nozzles with ratios of length to minimum internal diameter thatare very high, for example greater than about ten, tend to create a veryhigh pressure drop through the nozzle during use without significantlyimproving the degree of collimation of the jet and, therefore, are lesspreferred than nozzles having a ratio of length to minimum internaldiameter of an intermediate value, for example about six.

[0107]FIG. 3b shows the distal portion of pressure lumen 184 providing anozzle 186 that is similar in configuration to nozzle 174 shown in FIG.3a. Pressure lumen 184, however, is curved near its distal end so thatjet opening 188 emits a liquid jet having an axis 190 defining thedirection of its central region, which would be essentially parallel toa longitudinal axis of the proximal end of the surgical liquid jetinstrument to which pressure lumen 184 is connected. In addition to theillustrated embodiments shown in FIGS. 3a and 3 b, those of ordinaryskill in the art would readily appreciate that the pressure lumen andnozzle can be shaped and positioned to provide liquid jets directed in awide variety of desired angular orientations with respect to thelongitudinal axis of the proximal end or body of the surgicalinstrument.

[0108]FIG. 3c shows an alternative embodiment for forming a liquid jetnozzle in a pressure lumen. Nozzle region 194 in pressure lumen 192comprises a hole that is drilled or bored into a sidewall of the tubingcomprising pressure lumen 192. Nozzle 194 provides a jet opening 196that directs a fluid jet so that the central region of the liquid jet iscollinear to an axis 198 that is essentially transverse to thelongitudinal axis of pressure lumen 192. The embodiment shown in FIG. 3cis well suited for use in surgical instruments where a low profilepressure lumen that provides a nozzle region having a length to minimuminternal cross-sectional diameter ratio that is relatively small isdesired. As will be discussed in greater detail below, nozzles havingrelatively low length to minimum internal diameter ratios are generallypreferred for surgical instruments designed for utilization in asurrounding gaseous environment. Nozzle region 194 will have a lengththat comprises essentially a wall thickness of pressure lumen 192 in theregion adjacent to the nozzle 194. The size of jet opening 196 can beselected with respect to the thickness of pressure lumen 192 to providethe desired length to minimum internal diameter ratio for nozzle 194.For embodiments involving surgical instruments designed for utilizationin a gaseous environment, the preferred length to minimum internaldiameter ratio of nozzle 194 is not greater than about four, and morepreferably is not greater than about two. As opposed to nozzles havingrelatively large length to minimum internal diameter ratios, whichtypically emit a relatively focused and collimated liquid jet as a highpressure liquid streams through the nozzle, nozzles having a lowerlength to minimum internal diameter ratio typically emit a liquid jetthat is less collimated and more diverging in character, as shown inFIG. 3e.

[0109]FIG. 3d shows yet another embodiment for providing a nozzle in apressure lumen. Similar to FIG. 3c above, pressure lumen 198 in theillustrated embodiment includes a hole that is bored into a sidewall oftubing comprising the pressure lumen. Unlike the embodiment shown aboveis FIG. 3c, and in order to provide a nozzle 202 having an increasedlength to minimum internal diameter ratio, pressure lumen 198 includes anozzle insert 200 that is sealingly inserted into the bore formed in thesidewall of the lumen. Nozzle insert 200 can include a channel 204formed therein having a desired predetermined minimum internal diameterto provide a desired nozzle length to internal diameter ratio, which cangenerally exceed the nozzle length to diameter ratio possible for anozzle formed as in FIG. 3c above. Nozzle insert 200 may be formed fromthe same material as pressure lumen 198, for example stainless steel, ormay be formed from a variety of other materials having a hardness levelthat exceeds the material utilized for forming pressure lumen 198. Forexample, nozzle insert 200 may be made entirely, or at least in part,from a metal such as titanium, tungsten, vanadium, or other highhardness metals, or from a crystalline non-metallic material, such assapphire, diamond, etc., as apparent to those of ordinary skill in theart. In alternative embodiments, instead of providing a nozzle insert asshown, the evacuation lumen may be provided with a region of thesidewall having a wall thickness exceeding that of the wall thicknessoutside the region. The nozzle, in such embodiments, can be formed byproviding a hole through the region having an increased wall thickness.

[0110]FIG. 4 illustrates a preferred method, according to the invention,for forming the nozzles described above in FIGS. 3a and 3 b. Step 1 ofFIG. 4 entails providing a tubular conduit 210 for use in forming apressure lumen. As described above, the tubular conduit is typicallyformed of a biocompatible metal such as surgical stainless steel and isselected to have a burst strength sufficient to withstand thecontemplated liquid pressures (e.g., a burst strength of at least 50,000psig).

[0111] Step 2 of the method comprises necking down an end of conduit 210to form a necked region 212 having a reduced cross-sectional area, whichnecked region tapers into a jet nozzle region 214 having an essentiallyconstant internal cross-sectional area. Jet nozzle region 214 terminatesat its distal end in jet opening 220. Necked region 212 can be formed inconduit 210 by a variety of means known in the art, for example byswaging, crimping, or hotdrawing the distal end of conduit 210 to formnecked region 212 and jet nozzle region 214. At the end of Step 2,pressure lumen conduit 210 has an internal radius R , jet nozzle region214 has a minimum internal radius r, and jet nozzle region 214 isessentially co-linear with the axial center line 216 of the tubecomprising the pressure lumen 210 outside of necked region 212.

[0112] Step 3 of the method involves offsetting jet nozzle region 214with respect to tube 210 so that the axial center line 218 of nozzleregion 214 is offset from the axial center line 216 of tube 210 outsideof necked region 212, by a distance D=R−r, so that the jet nozzle region214 and the tubular conduit 210 abut each other along at least one line220 co-linear to an external surface of tubular conduit 210.

[0113] For embodiments where it is desired that at least a centralregion of the liquid jet emitted from jet opening 220 be directed in anorientation that is not parallel with axis 216, jet nozzle region 214may be bent with respect to axis 216 as shown in optional Step 4. Intypical embodiments, nozzle region 214 is bent so that the axial centerline 218 of jet nozzle region 214 forms an angle with respect to axis216 that is between 45 and 115 degrees, more typically between about 80and 100 degrees, and most typically about 90 degrees. Also preferablynozzle region 214 is bent with respect to tube 210 so that essentiallyno portion of jet nozzle region 214 projects radially beyond a perimeterthat is defined by an outer surface of tube 210 outside of necked region212. In addition to providing a method for forming liquid jet nozzlesthat have a relatively large length to minimum diameter ratio and thatare relatively easy and inexpensive to manufacture, the inventive methodalso provides a pressure lumen having a maximum cross-sectional profilethat does not exceed the diameter of the tubing comprising the pressurelumen. In addition, the nozzles formed by the method outlined in FIG. 4also advantageously provide improved efficiency for forming a liquid jetas a high pressure liquid streams through the nozzle. The efficiency offorming the liquid jet is improved over nozzle designs comprising, forexample, a hole bored in the side of a lumen, due to the fact thatnecked region 212 provides a smooth tapering flow path for the liquidflowing into nozzle region 214, thus reducing turbulence, recirculatingflow patterns, and friction at the jet nozzle inlet. This effect isknown in the fluid mechanical arts as the “vena contracta” effect andcan improve fluid flow efficiencies through nozzles by as much as 30%.

[0114] The present invention provides surgical liquid jet instrumentswhich are specifically designed and constructed for use in a particularsurgical environment. Specifically, in some embodiments, the presentinvention provides surgical liquid jet instrument designs that aretailored to provide highly desirable performance characteristics insurgical operating environments where the liquid jet is submerged in aliquid environment when the instrument is in operation, and, in otherembodiments, the present invention provides surgical liquid jetinstrument designs that are tailored to provide highly desirableperformance characteristics in surgical operating environments where theliquid jet is surrounded by a gaseous environment when the instrument isin operation. More specifically, the invention provides surgical liquidjet instruments including pressure lumen and evacuation lumen that areshaped, and positioned relative to each other, to establish certainpredetermined geometric relationships between the jet forming componentsand jet-receiving components that are specifically selected to providethe desired performance characteristics of the instrument in a liquid orgaseous surgical environment. Importantly, the above mentioned geometricrelationships and design characteristics are substantially different forinstruments that are designed for use in a liquid environment whencompared to instruments that are designed for use in a gaseousenvironment.

[0115] Reference is made in FIG. 5a for describing the operation anddesign characteristics of preferred devices for use in forming a liquidjet that is submerged in a surrounding liquid-containing surgicalenvironment. FIG. 5a shows a partially cutaway view of the distal endsof pressure lumen 230 and evacuation lumen 240, which can form part of asurgical instrument, for example such as that shown previously in FIG.2a. Prior to operation, the distal ends of pressure lumen 230 andevacuation lumen 240 would be inserted into the operating field and atleast partially submersed in a liquid 244 therein so that at leastnozzle 232 and jet-receiving opening 234 are completely surrounded byliquid 244. When the instrument is in operation, liquid under highpressure is delivered via pressure lumen 230 to nozzle 232, causing jetopening 236 to create a liquid jet 238 as the high pressure liquidstreams therethrough. As mentioned previously, for embodiments where theliquid jet 238 is formed in a surrounding liquid environment 244, it ispreferred that the jet 238 is substantially collimated as it exits jetopening 236. The more collimated a liquid jet, the less the liquid jetwill diverge or disperse as it traverses the gap between jet opening 236and jet-receiving opening 234. Thus, a highly collimated jet will have across-sectional shape and area at the jet-receiving opening 234 that issubstantially similar to the cross-sectional shape and area of theliquid jet at jet opening 236.

[0116] As discussed previously, the pressure of the high pressure liquidsupplied to nozzle 232 for forming the liquid jet 238 depends on theparticular design of nozzle 232 and the hardness/toughness of tissue ormaterial to be cut or ablated. Typically, the liquid at high pressure issupplied to jet opening 236 at a pressure of at least 500 psig, in otherembodiments at a pressure of at least about 5,000 psig, and still otherembodiments at a pressure of at least about 15,000 psig, and still otherembodiments at a pressure of at least 30,000 psig, and in yet stillother embodiments at a pressure of at least about 50,000 psig. Also asdiscussed previously, for embodiments where a collimated jet is desired,nozzle 232 preferably has a length to minimum internal diameter ratio ofat least about four, more preferably at least about six, and in otherembodiments at least about ten. Jet opening 236 typically has a circularcross-sectional area, but may, in other embodiments, have othercross-sectional shapes, such as rectangular, oval, slit-like, etc., forforming jets having different shapes for specific desired purposes. Inpreferred embodiments, jet opening 236 has an internal diameter ofbetween about 0.001 and about 0.02′ inches, more preferably betweenabout 0.003 and about 0.01′ inches, and most preferably about 0.005inches.

[0117] Liquid jet 238, which is collimated as it exits jet opening 236,tends to create a visible, opaque entrainment region 242 surroundingliquid jet 238. Entrainment region 242 is comprised of rapidly movingliquid, which is entrained and driven by the kinetic energy of liquidjet 238. Liquid jet 238, as it rapidly moves through liquid environment244, also tends to create a zone of low pressure, which is essentiallycoextensive with entrainment region 242. In typical embodimentsinvolving high pressure liquids and rapidly moving liquid jets, thepressure in entrainment region/low pressure zone 242 will be lower thanthe vapor pressure of the surrounding liquid in liquid environment 244,thus causing cavitation of the liquid in entrainment region 242 and aresulting formation of an abundance of extremely small gas bubbles 246within the liquid in the entrainment region 242, making the regionvisually opaque.

[0118] As discussed previously, it is desired, in preferred embodiments,for safety and performance that the instrument be designed to reduce,and preferably eliminate, undesirable effects, such as blow-by of theliquid jet, plugging of the jet-receiving opening and the evacuationlumen, and inefficient tissue/debris entrainment and removal. Also, aspreviously mentioned, in preferred embodiments, it is desirable thatablated tissue and debris be evacuated from the surgical site throughthe evacuation lumen, without the need for a source of external suctionto be applied to the proximal end of the evacuation lumen. In order toprovide the above-mentioned characteristics, the inventive surgicalinstruments for use in a liquid environment can include an evacuationlumen having specifically selected predetermined shapes andconfigurations, which is positionable relative to the jet opening at aspecific predetermined distance. Specifically, in preferred embodiments,jet-receiving opening 234 is positioned, when the instrument is inoperation, opposite jet opening 236, at a predetermined distance ltherefrom, and provided in a nozzle 232 having a length to minimumdiameter ratio so that essentially all of the fluid in liquid jet 238enters jet-receiving opening 234. As discussed above, liquid jet 238will tend to create entrainment region 242 surrounding the liquid jet238 when the instrument is in operation. Entrainment region 242 willtypically be symmetrically deposed around liquid jet 238 and will tendto diverge in a direction from jet opening 236 to jet-receiving opening234. In typical embodiments where jet opening 236 is circular in shape,entrainment region 242 will have a truncated cone shape, having atruncated apex at jet opening 236 and a base defined as a cross sectionof the cone at the plane of jet-receiving opening 234. In preferredembodiments, the base of entrainment region 242 occupies between about50% and about 100% of the cross-sectional area of jet-receiving opening234 when the instrument is in operation, more preferably the entrainmentregion occupies at least about 75%, more preferably still at least about90%, and most preferably at least about 95% of the cross-sectional areaof jet-receiving opening 234 when the instrument is in operation.

[0119] As shown in FIG. 5c, the cross-sectional area of thejet-receiving opening 234 required to ensure that the entrainment region242 occupies the desired relative fraction of the cross-sectional areaof the jet-receiving opening 234, as discussed above, is functionallyrelated to the chosen predetermined distance l between the jet opening232 and the jet-receiving opening 234 and the degree of divergencecharacterizing the entrainment zone (represented by angle φ in FIG. 5c).Specifically, the desired cross-sectional radius b of the base of theentrainment region 242 at the jet-receiving opening 234 is related topredetermined distance l and the degree of divergence of the entrainmentregion by b=l tan φ. Predetermined distance l is typically selectedbased on the desired use of the surgical instrument, dictating arequired fluid path cutting/ablating length. Based upon this desiredpredetermined distance l, the required size of the jet-receiving opening234 is typically determined experimentally by submersing the pressurelumen 230 and nozzle 232 in a liquid environment 244, forming a liquidjet 238 by supplying a liquid to the nozzle 232 at a desiredpredetermined pressure, and visually observing the size of theentrainment region 242 or cavitation cone created around the liquid jet238, and estimating angle φ from the observations.

[0120] As mentioned above, the predetermined separation distance lbetween the jet opening 236 and the jet-receiving opening 234 dependsupon the requirements of the particular surgical procedure for which thesurgical instrument is used; however, for some typical embodiments, thepredetermined distance will have a maximum value of about 1 cm, forother typical embodiments, about 5 mm, and for yet other typicalembodiments, about 1 mm. The jet-receiving opening 234 typically willhave a diameter of between about 0.01 and about 0.2 inches, in otherembodiments between about 0.03 and about 0.1 inches, and in somepreferred embodiments a diameter of about 0.06 inches.

[0121] Referring again to FIG. 5a, a preferred configuration forevacuation lumen 240 will now be described. Preferred embodiments ofevacuation lumen 240 for use in surgical instruments intended to beoperated in a liquid environment include a maceration region 246 withinand/or downstream and in close proximity to the inlet to evacuationlumen 240 at jet-receiving opening 234. Maceration region 246 is definedas a region that contains a liquid undergoing intensely turbulent flowand impacting an internal surface of the evacuation lumen at an acuteangle, thus creating significant impacting forces capable of maceratingentrained material/tissue, when the instrument is in operation. Thecombination of the intensely turbulent flow of the liquid in macerationregion 246 and the impacting forces of liquid jet 238 and the liquid inentrainment region 242 against the wall of evacuation lumen 240 enablethe liquid within the maceration region to macerate at least a portionof any tissue or material entrained by the liquid in entrainment region242 into a plurality of small particles. In preferred embodiments, themaceration region is able to macerate a substantial fraction (i.e., themajority of) the entrained tissue into a plurality of small particles.In most preferred embodiments, the plurality of particles at leastpartially comprises a plurality of microscopic particles too small to beseen unaided with the human eye. In all cases, the particles should besmall enough to pass through evacuation lumen 240 without plugging theevacuation lumen, when the instrument is in operation.

[0122] In order to provide a maceration region, evacuation lumen 240preferably includes a jet-deflecting portion 248 that is locatedadjacent to and downstream of jet-receiving opening 234. Jet-deflectingregion 248 may be either a straight surface that is angled with respectto the direction of at least a central portion of liquid jet 238, or inpreferred embodiments, jet-deflecting region 248 comprises a smoothlycurved surface upon which at least a portion of liquid jet 238 impinges,where the curved surface is shaped to deflect at least a portion, andpreferably all of the liquid jet 238 and liquid comprising entrainmentregion 242 in a direction that is essentially parallel to thelongitudinal axis 250 of evacuation lumen 240 in the region proximal tothe jet-deflecting region 248. In preferred embodiments, the radius ofcurvature of the curved surface defining jet-deflecting region 248 isessentially constant, having a value of between about 1 and 20 times theinternal diameter of evacuation lumen 240. In the most preferredembodiments, as shown in FIG. 5a, the radius of curvature of the curvedsurface defining jet-deflecting region 248 is essentially equal to theinternal diameter of evacuation lumen 240 at jet-deflecting region 248,so that essentially no portion of jet-receiving opening 234 projectsradially beyond a perimeter defined by an outer surface 252 of a portionof the evacuation lumen located proximal and adjacent to jet-deflectingregion 248. It is also generally preferable for the surgical instrumentsprovided by the invention that the liquid jet be directed into thejet-receiving opening so that a direction of at least a central portionof the liquid jet forms an angle of no greater than 10 degrees withrespect to a line normal (i.e., perpendicular) to a plane defining(i.e., co-planar to) the jet-receiving opening. In the most preferredembodiments, the central portion of the liquid jet is essentiallyparallel to a line that is normal to the plane defining thejet-receiving opening.

[0123] In order to provide effective eductor pump action of evacuationlumen 240, in some embodiments, evacuation lumen 240 will have anessentially constant internal cross-sectional area from jet-receivingopening 234 to a position that is proximal to the distal end of thesurgical instrument where the proximal end of the evacuation lumen islocated. In other embodiments, eductor pump action can be enhanced byproviding an evacuation lumen having an essentially constantcross-sectional area and having a jet-receiving opening, which has across-sectional area that is less than the cross-sectional area of theevacuation lumen (i.e., the internal cross-sectional area of theevacuation lumen has a minimum value at the jet-receiving opening). Inyet other embodiments, eductor pump action can be enhanced by providingan evacuation lumen having an internal cross-sectional area whichincreases continuously from a minimum value at the jet-receiving openingto a maximum value at a predetermined position located proximal to thejet-receiving opening. In such embodiments, this maximum value of theinternal cross-sectional area should be essentially constant forpositions within the evacuation lumen that are proximal to theabove-mentioned predetermined position. In each of the above-mentionedembodiments, there are preferably essentially no reductions in theinternal cross-sectional area of the evacuation lumen at any positionproximal and/or downstream of the maceration region described above.

[0124]FIG. 5b shows an alternative design embodiment for theconstruction of the evacuation lumen for surgical instruments designedfor use in a liquid surgical environment. Evacuation lumen 260 includesa constriction 262 in the internal cross-sectional area of theevacuation lumen. The constriction 262 is located proximal tojet-receiving opening 264, and is preferably positioned immediatelyproximal and adjacent to maceration region 266. In operation, theconstriction 262 in the evacuation lumen 260 will act as a venturi asliquid within the evacuation lumen flows through the constriction, thusenhancing the eductor pump action of evacuation lumen 260. In theillustrated embodiment, constriction 262 comprises a pinch 268 in thesidewall of the tubing conduit comprising evacuation lumen 260. Inpreferred embodiments, the cross-sectional area of constriction 262should be between about three and about eight times the cross-sectionalarea of jet-opening 270 in nozzle 272.

[0125] Referring again to FIG. 5a, evacuation lumen 240 is shaped andpositioned relative to pressure lumen 230 so that at least a centralportion of liquid jet 238 is directed into jet-receiving opening 234 ina direction forming a non-zero angle with respect to (i.e. nonparallelwith) the longitudinal axis 250 of evacuation lumen 240 in a regionproximal to jet-deflecting region 248. In some embodiments, this anglecan be between about 45 and 115 degrees, in other embodiments betweenabout 80 and 100 degrees, and in some preferred embodiments, asillustrated, the angle can be about 90 degrees. In other embodiments,involving surgical instruments designed for use in a liquid environment,the direction of at least the central portion of the liquid jet andlongitudinal axis of the evacuation lumen in a region proximal to thejet-deflecting region may be essentially parallel, as shown for exampleby the embodiment illustrated in FIG. 7d.

[0126]FIGS. 6a and 6 b illustrate preferred arrangements for liquid jetsurgical instruments designed for use in a surrounding gaseousenvironment. Referring to FIG. 6a, a partially cutaway view of thedistal ends of a pressure lumen 280 and evacuation lumen 282 of asurgical liquid jet instrument for use in gaseous environment 284 isshown. For instruments designed for use in a gaseous environment, nozzle286 preferably has a lower length to minimum internal diameter ratiothan preferred nozzles employed for instruments designed for use in aliquid environment. As discussed previously, preferably nozzle 286,constructed in the illustrated embodiment as a hole bored in a sidewallof pressure lumen 280, has a length to minimum internal diameter rationot greater than about four, and more preferably not greater than abouttwo Unlike the relatively collimated liquid jets preferred forinstruments for use in a liquid environment, instruments for use in agaseous environment preferably create a diverging liquid jet as a highpressure liquid flows through the nozzle. Preferably, liquid jet 288emitted from jet opening 290, when the instrument is in operation, is adiverging jet creating an entrainment region comprised of a divergingzone of liquid droplets 292 moving through gaseous environment 284. Thezone of liquid droplets comprising liquid jet 288 will tend to create aregion of relatively low gas pressure, when compared to the pressure inthe gas surrounding the liquid jet region 288, that will have a tendencyto entrain and draw tissue and material into an entrainment region thatis essentially co-extensive with jet region 288.

[0127] Of critical concern for most applications employing liquid jetsurgical instruments in a gaseous environment is minimizing, andpreferably eliminating, misting and back spray of the liquid jet fromthe jet-receiving opening. Such misting or back spray can cause poorvisualization of the surgical field, in addition to potentially creatinginfectious and/or undesirable aerosolization of material into thesurrounding gaseous environment. In order to avoid back spray or mistingfrom the evacuation lumen, evacuation lumen 282 is preferablyessentially straight at its distal end so that an axis 294 defining thedirection of at least a central region of liquid jet 288 is essentiallyco-linear with the longitudinal axis of the distal end of evacuationlumen 282. With such configurations, essentially complete tissuemaceration is not as critical as for instruments creating liquid jetshaving central regions directed at steep angles (e.g. between 45 and 135degrees) to the longitudinal axis of the distal end of evacuation lumen(e.g. as shown above in FIG. 5a) because material and debris typicallyhave a lower tendency to accumulate in, and potentially clog, anessentially straight distal end of an evacuation lumen.

[0128] As mentioned above, liquid jet 288 is preferably a diverging jet,which diverges as it travels from jet opening 290 to jet-receivingopening 296. Diverging jet 288 will have an apex at jet opening 290 and,for essentially circular jet opening shapes, will typically have atruncated cone shape, where the truncated apex of the cone is located atjet opening 290 and the base of the cone is defined as the planar crosssection of the cone at jet-receiving opening 296. As was previously thecase for surgical instruments designed for use in a liquid environment,preferred embodiments of surgical instruments designed for use in agaseous environment provide an evacuation lumen shaped and positionedrelative to the jet opening, when the instrument is in operation, sothat the base of the liquid jet entrainment region occupies betweenabout 50% and about 100% of the cross-sectional area of thejet-receiving opening, more preferably the entrainment region occupiesat least about 75%, even more preferably at least about 90%, and mostpreferably at least about 95% of the cross-sectional area of thejet-receiving opening. As was previously described in the context ofinstruments for use in a liquid environment, the size of jet-receivingopening 296 can be selected based upon the desired separation distancebetween jet opening 290 and jet-receiving opening 296 and the length tominimum internal diameter ratio of nozzle 286, which dictates the degreeof divergence of liquid jet 288. Analogous to the geometricalrelationships discussed previously in the context of FIG. 5c, therelationship between the radius of liquid jet entrainment region 288 atjet-receiving opening 296 is related to separation distance l betweenjet opening 290 and jet-receiving opening 296 as b=l tan φ where φdefines the divergence angle of liquid jet 288, which is related to thelength to minimum diameter ratio of nozzle 286, and b is defined as theradius of the base of the liquid jet entrainment region 288. Asdescribed before, the desired size of jet-receiving opening 296 istypically determined experimentally, for example by creating a liquidjet in a gaseous environment using a desired liquid supply pressure anda given nozzle configuration, visually observing the diverging liquidjet formed, and estimating angle φ from the observation. The appropriatejet-receiving opening size can then be selected based on φ and thedesired separation distance l.

[0129] In preferred embodiments, it is also desirable to shape andposition evacuation lumen 282 with respect to jet opening 290 so thatthe cross-sectional shape and area of liquid jet 288 at a given location298 within evacuation lumen 282 is essentially the same as the internalcross-sectional shape and area of evacuation lumen 282 at given location298. Given location 298 may coincide with jet-receiving opening 296 ormay be located proximal to jet-receiving opening 296. For embodimentswhere given location 298 is located proximal to jet-receiving opening296, preferably the given location 298 is no greater than about 5 mmproximal to jet-receiving opening 296. By shaping and positioningevacuation lumen 282 in this fashion, it is assured that liquid jet 288completely fills the cross-sectional area of the evacuation lumen 282 ata position at or near its distal entrance, thus essentially eliminatingback spray and misting and improving evacuation via eductor pump action.

[0130] Evacuation lumen 282 may have an essentially constant internalcross-sectional area, may have an essentially cross-sectional area witha jet-receiving opening having a cross-sectional area that is less thanthe cross-sectional area of evacuation lumen 282, or may have aninternal cross-sectional area which increases continuously from aminimum value at jet-receiving opening 296 to a maximum value at apredetermined position proximal to jet-receiving opening 296, which thenremains essentially constant for positions proximal to the predeterminedposition. Alternatively, as shown in FIG. 6b, the instrument may includean evacuation lumen 300 having a constriction 302 located proximal to ajet-receiving opening 304, which constriction acts as a venturi toenhance the eductor pump action of evacuation lumen 300. For embodimentsincluding a constriction in the evacuation lumen, it is preferred thatthe liquid jet 306 contact the inner surface of evacuation lumen 300 ata given location 308 that is located distal to constriction 302. Thecross-sectional area of constriction 302 is preferably between aboutthree and fifteen times greater than the cross-sectional area of jetopening 303 in nozzle 305.

[0131] It should be understood that while certain preferred embodimentsof the inventive liquid-jet surgical instruments for use in a liquidenvironment have been described as including an evacuation lumenconstructed and positioned to provide a jet-deflecting surface uponwhich a liquid jet impinges, and while certain preferred embodiments ofthe inventive liquid-jet surgical instruments for use in a gaseousenvironment have been described as providing an evacuation lumen that isessentially straight and does not include a jet-deflecting surface, theliquid jet surgical instruments within the scope of the presentinvention are not so limited. Specifically, configurations such as thoseshown in FIGS. 5a and 5 b could be employed for a surgical instrumentintended for use in a gaseous environment in an application where thepotential creation of misting and/or back spray is not critical.Similarly, the configurations illustrated in FIGS. 6a and 6 b couldalternatively be employed for use in a surgical instrument intended tobe used in a liquid environment in applications where the essentiallyco-axial orientation of the liquid jet is acceptable for allowing accessto the desired surgical site and where essentially complete tissuemaceration is not critical.

[0132]FIG. 7 illustrates a variety of contemplated embodiments for thedistal end of a liquid jet surgical instrument, according to theinvention. FIG. 7a shows a partially cutaway view of the distal end ofthe surgical instrument having a sheath 310 from which a pressure lumen312 extends distally. Evacuation lumen 314 is completely containedwithin and surrounded by sheath 310. During operation, a liquid jet isemitted from jet opening 316 and directed into jet-receiving opening 318such that at least a central portion of the liquid jet is directedproximally and parallel to a longitudinal axis of sheath 310. Theconfiguration shown in FIG. 7a is well suited for surgical instrumentsintended for use in gaseous environments and may also be useful forsurgical instruments intended for use in liquid environments, whereextensive maceration of tissue is not critical.

[0133]FIGS. 7b and 7 c show two embodiments of the distal end of asurgical liquid jet instrument according to the invention where thedistal end of sheath 320 essentially completely surrounds both pressurelumen 322 and evacuation lumen 324. The liquid jet path length iscreated in the instruments by providing a notch 326 at the distal end ofsheath 320 where the proximal surface of notch 326 includes ajet-receiving opening 328, and the distal end of notch 326 includes ajet opening 330. In some embodiments, sheath 320 may be constructed froma flexible material, such as a polymeric material, and theconfigurations shown in FIGS. 7b and 7 c may comprise part of a liquidjet surgical instrument configured as an elongated catheter. Theconfiguration shown in FIGS. 7b and 7 c are substantially similar exceptthat in FIG. 7b, the liquid jet 331 emitted from jet opening 330 has acentral region directed proximally and parallel to the longitudinal axisof sheath 320, and in contrast, the central region of the liquid jet 331for the configuration shown in FIG. 7c, is directed towardsjet-receiving opening 328 at an angle of about 45 degrees with respectto the longitudinal axis of sheath 320.

[0134]FIG. 7d illustrates an embodiment of a distal end of a surgicalliquid jet instrument according to the invention that is capable ofproviding a maceration zone for a liquid jet 341 whose central region isdirected proximally and essentially parallel to the longitudinal axis ofsheath 340 and the proximal end of the instrument to which it would beconnected. The sheath 340 has a distal end from which projects pressurelumen 342 and evacuation lumen 344. Evacuation lumen 344 has two curvedregions 347, 350 near its distal end, the second curved region 350 beingadjacent to jet-receiving opening 348 and providing a jet-deflectingregion.

[0135]FIG. 7e illustrates an embodiment for a distal end of a surgicalinstrument according to the invention that is similar to that describedpreviously in FIG. 5a, except that the central region of the liquid jet361 formed by the nozzle 363 in the configuration of FIG. 7e has adirection forming an angle with respect to the longitudinal axis ofevacuation lumen 360 and sheath 362 that is approximately 45 degrees, asopposed to about 90 degrees for the configuration shown in FIG. 5a.

[0136] The invention also provides various embodiments of surgicalliquid jet instruments having distal ends for insertion into a surgicaloperating space that have a predetermined contour and size that areselected to facilitate inserting the distal end into the confinedsurgical operating space. Preferred embodiments of such surgicalinstruments provided by the invention include mechanisms for creatingrelative motion between the pressure lumen and evacuation lumen in orderto change the orientation, positioning, and/or configuration of thelumen with respect to each other, for example to increase a separationdistance between the jet opening and the jet-receiving opening.Embodiments of surgical liquid jet instruments having actuatingmechanisms, as provided by the invention, typically enable the distalend of the instruments to be inserted into a surgical operating space inan undeployed configuration, and subsequently deployed by an operator toprovide a desired separation distance between the jet opening and thejet-receiving opening in order to yield a desired liquid jet pathlength. Typically, embodiments involving deployable liquid jet surgicalinstruments are directed to surgical applications involving confinedregions within the body of a patient, such as joint capsules. In manysuch embodiments, the surgical environment surrounding the distal end ofthe instrument, when it is in operation, is a liquid environment.

[0137]FIGS. 8a-8 c illustrate one embodiment of a deployable liquid jetsurgical instrument according to the invention. FIG. 8a shows aninstrument 380 with distal end 382 in an undeployed configuration.Distal end 382 of instrument 380 includes pressure lumen 384 andevacuation lumen 386, which protrude from the distal end of sheath 388.In the undeployed configuration shown, pressure lumen 384 and evacuationlumen 386 are essentially co-directional along their length, within thedistal end 382 of instrument 380, and, therefore, provide a minimumcross-sectional dimension for distal end 382 of instrument 380. Sheath388 also includes a region of reduced cross-section 390 near its distalend in order to provide a reduced cross-sectional dimension ofinstrument 380 near distal end 382. The contour and size of distal end382 can be selected to facilitate inserting the distal end 382 ofinstrument 380 into a confined surgical operating space for a particularsurgical procedure. For example, in embodiments where instrument 380 isused to perform a surgical procedure in the human knee, preferably thedistal end 382 of surgical instrument 380 has at least onecross-sectional dimension that does not exceed about 2.8 mm whensurgical instrument 380 is in the undeployed configuration. Whenutilizing such an instrument for a surgical procedure on the knee, thecross-sectional dimension of the undeployed distal end not exceeding 2.8mm is oriented essentially normal to the plane of the tibial plateau inorder to facilitate insertion of the distal end into the knee. Distalend 382 may also include a region 392 near the extreme distal end ofinstrument 380 that is angularly displaced from the longitudinal axis ofsheath 388 by a desired angle α. This angle may be selected to improvethe ease of insertion of the device into a particular confined surgicaloperating space within the body of a patient. For example, forembodiments where surgical instrument 380 is used to perform a surgicalprocedure within a joint capsule comprising a human knee, the maximumangle α of angled or curved region 392 of distal end 382 with respect tothe longitudinal axis of sheath 388 or body 394 of surgical instrument380 is preferably about 15 degrees.

[0138] Body 394 of surgical instrument 380 includes a grasping region396 configured to fit within the hand of an operator. Body 394 may beconstructed of a variety of materials, and is preferably constructed ofa resilient, inexpensive, easily moldable polymeric material, which may,in certain embodiments, be injection molded or cast to form the body.Various polymeric materials may be used to form body 394, as would beapparent to those of ordinary skill in the art, including but notlimited to, polyethylene, polypropylene, polystyrene, polycarbonate,polyacrylate, polyvinyl chloride, phenolic polymer, nylon, and others,as well as mixtures, copolymers, and combinations thereof, etc. Aspreviously discussed, instrument 380 is preferably constructed fromrelatively inexpensive and easy to assemble materials, so that theentire instrument may be disposable after a single use. Body 394 ofsurgical instrument of 380 also includes an actuating element 398, whichcomprises a rotatable knob, that is controllable by the hand of anoperator and useful for deploying distal end 382 of instrument 380, asdescribed in more detail below.

[0139]FIG. 8b shows surgical instrument 380 in the deployedconfiguration. Surgical instrument 380 can be deployed by rotatingactuating element 398 in a clockwise direction causing a correspondingrotation of the distal end of pressure lumen 384 with respect toevacuation lumen 386. The direction of rotation of the distal end ofpressure lumen 384 is indicated in the figure by arrow 400. Uponrotation of pressure lumen 384 with respect to body 394 of instrument380, the separation distance 402 defining a liquid jet path lengthbetween jet opening 404 and jet-receiving opening 406 increases from avalue of essentially zero, when instrument 380 is in the undeployedposition, to a desired predetermined distance defined by the limits oftravel of actuating element 398. In some embodiments, the actuatingelement may include one or more detents constructed to hold theactuating element at one or more intermediate positions within thelimits of travel to allow the predetermined distance to be adjusted to avariety of predetermined values. The structure of such detents is wellunderstood by those of ordinary skill in the art and will not bedescribed in detail herein. Such detents may also be provided as part ofthe actuating mechanisms of the embodiments of deployable surgicalinstruments described below. In preferred embodiments of the deployablesurgical liquid-jet instruments according to the invention, theactuating element is constructed to have a continuous range of motionover its limits of travel so that the predetermined distance definingthe jet path length is continuously and infinitely adjustable by theoperator. This desired predetermined distance can be selected to providea desired liquid jet cutting/ablating path length for a particularsurgical procedure. For example, for surgical procedures performedwithin a human joint capsule, such as a human knee, the maximumseparation distance between jet opening 404 and jet-receiving opening406 should preferably not exceed about 4 mm.

[0140]FIG. 8c more clearly shows the internal features of surgicalinstrument 380. Evacuation lumen 386 is fixably mounted within body 394of surgical instrument 380 so that it is essentially immobile withrespect to body 394. Proximal end 408 of evacuation lumen 386 comprisesa barbed fitting to which is coupled low pressure evacuation conduit410. Pressure lumen 384 is rotatably mounted within sheath 388 and body394 of instrument 380 and is fixably mounted to actuating element 398.The proximal end 412 of pressure lumen 384 is coupled to high pressureliquid supply conduit 416 via high pressure tubing coupler 414, asdescribed previously. Body 394 of surgical instrument 380 includes arotatable coupling 418 through which high pressure liquid supply conduit416 traverses. Rotatable coupling 418 is configured to allow conduit 416and pressure lumen 384 to rotate with respect to body 394 upon actuationof rotatable knob 398.

[0141]FIG. 8d shows a cross-sectional view of sheath 388 of surgicalinstrument 380. In the embodiment illustrated, pressure lumen 384 has asemi-hemispherical shape having a flat region 420 positioned near thecenter of sheath 388. Evacuation lumen 386 has an essentiallyrectangular cross-sectional shape with a flattened region 422 that isco-directional and in contact with flattened region 420 of pressurelumen 384. The illustrated, non-circular configuration of lumens 384 and386 can serve a dual purpose. First, the non-circular shape can enablethe reduction of the overall cross-sectional dimension of distal end 382of instrument 380, when in the undeployed configuration. In addition,flat regions 420 and 422 impart desirable lateral stiffness to lumens384 and 386 to prevent undesirable bending of the lumens upon contactwith surfaces within an operating field, which bending can causemisdirection of the liquid jet and potential unintended tissue damage.In an alternative embodiment, pressure lumen 384 and/or evacuation lumen386 may have an essentially circular cross-sectional shape and may eachbe deployed within separate channels within the sheath for additionalsupport, such as shown in FIG. 2a previously.

[0142]FIG. 9 shows an alternative embodiment for a deployable surgicalliquid jet instrument where deployment is effected via a longitudinalmovement of at least one of the lumen with respect to the body of theinstrument. Surgical instrument 430 is shown with the distal end 446 inthe deployed configuration. Instrument 430 includes an evacuation lumen434 that is fixably mounted within body 438 and/or sheath 436 so thatthe evacuation lumen 434 is essentially immovable with respect to body438. Surgical instrument 430 also includes a pressure lumen 432 which isslidably mounted within sheath 436 and body 438 to allow the distal endof pressure lumen 432 to slide in and out of the distal end of sheath436 upon actuation of slidable lever 440 by an operator of theinstrument. Slidable lever 440 is pivotally mounted to body 438 viaattachment to pin element 442. Pressure lumen 432 includes two cammingelements 444 fixed thereto, which are mounted so that end 446 ofslidable lever 440 is located between camming elements 444. Uponmovement of slidable lever 440, pressure lumen 432 is movedlongitudinally within sheath 436 and body 438 in order to deploy thedistal end of pressure lumen 432.

[0143]FIG. 10 shows an alternative embodiment of a deployable surgicalinstrument, where the instrument is deployed by longitudinal movement ofat least one lumen with respect to the body of the instrument. Surgicalinstrument 450 is shown in the deployed configuration and includespressure lumen 452 which is fixably mounted within body 456 and/orsheath 454, and which is essentially immobile with respect to body 456.Surgical instrument 450 further includes an evacuation lumen 458 whichis longitudinally movable with respect to body 456 via slidable lever460, which is mounted within body 456. Upon an operator moving slidablelever 460 distally with respect to body 456 from the indicated positionin the figure, the distal end of evacuation lumen 458 is withdrawn intothe distal end of sheath 454. Upon deployment, the distal end ofevacuation lumen 458 emerges distally from the distal end of sheath 454and also moves laterally, indicated by arrows 462, with respect to thedistal end of pressure lumen 452, in order to create a separationdistance between the jet opening and the jet-receiving opening. In orderto provide the necessary lateral movement of the distal end ofevacuation lumen 458 upon deployment of instrument 450, the distal endof evacuation lumen 458 can be constructed from a shape memory springsteel material, or may include a hinged joint, or flexible, bendableportion, or other means for pivoting evacuation lumen 458 at point 464so as to create a lateral movement of the evacuation lumen when theevacuation lumen is longitudinally deployed from sheath 454. In otherembodiments, the lateral motion of the distal end of evacuation lumen458 upon deployment may be controllable by an operator of the instrumentvia manipulation of an element (not shown) provided on the body 456 ofthe instrument 450 that is connected to the distal end of the evacuationlumen 458. For example, one or more wires may be provided, which areattached to a controllable element provided on the body 456 of theinstrument 450 and which pass through sheath 454, and that are attachedat their distal ends to the longitudinally movable distal end ofevacuation lumen 458. In such embodiments, creation of a tension on thewire or wires via actuation of an element on the body of the instrumentcould be used to create a force on the movable tip of evacuation lumen458 in order to move it laterally with respect to the distal end ofpressure lumen 452, upon deployment of the instrument. Those of ordinaryskill in the art would readily appreciate that there are many mechanismsby which the distal end of evacuation lumen 458 may be longitudinallyand laterally deployed that are within the scope and spirit of thepresent invention.

[0144] An alternative embodiment for a rotatably deployed surgicalliquid jet instrument is shown in FIGS. 11a-11 f. Referring to FIG. 11a,surgical instrument 470 includes a body 472 having a grasping region 474configured to be held within the hand of an operator and an actuatingelement 476 that comprises a slidable sleeve or collar, which is used todeploy the distal end 478 of surgical instrument 470. Slidable sleeve476 is positioned to be easily actuated by a single hand of an operatorof instrument 470. Slidable sleeve 476 can enable the operator to holdbody 472 in at least two different hand/grasping region 474orientations, so that the operator can actuate slidable sleeve 476 whileholding body 472 in either of the at least two hand/grasping region 474orientations. For example, an operator can grip body 472 in a handposition where the thumb of the operator is located near the distal endof gripping region 474. In such position, the operator can actuateslidable sleeve 476 by moving the slidable sleeve with her thumb. In asecond hand/grasping region orientation, the operator can grip body 472,for example, with her thumb positioned toward the proximal end of body472, while actuating slidable sleeve 476 via one or more of the otherfour fingers of her hand.

[0145] Surgical instrument 470 also includes a component 480 that isrotatably mounted within body 472. Rotatably mounted component 480 istypically a cylindrically-shaped sleeve, which may be attached to, orform part of, sheath 482. Distal end 478 of surgical instrument 470 isshown in FIG. 11a in an undeployed configuration. Sliding sleeve 476 inthe direction of arrows 484 causes a rotational motion of rotatablymounted component 480 in the direction shown by arrows 486, which, inturn, causes a rotation of evacuation lumen 490 about a longitudinalaxis of sheath 482, which is essentially parallel to the longitudinalaxis of body 472 and the longitudinal axis of the portion of evacuationlumen 490 within sheath 482. In other embodiments, upon deployment,evacuation lumen 490 may rotate about the longitudinal axis of sheath482, which is essentially collinear to the longitudinal axis to of theportion of evacuation lumen 490 within sheath 482, both of which axesare essentially parallel to the longitudinal axis of body 472. In yetalternative embodiments, instead of evacuation lumen 490 rotating upondeployment of instrument 470, evacuation lumen 490 may instead beimmobile with respect to body 472 and pressure lumen 488 may rotate uponactuation of slidable sleeve 476.

[0146] The distal end of surgical instrument 470 is shown in greaterdetail in FIGS. 11b and 11 c. FIGS. 11b and 11 c also show sheath 482and rotatably mounted component 480 in greater detail. Distal end 478 ofsurgical instrument 470 is shown in FIG. 11b in the undeployed positionand in FIG. 11c in the deployed position. In the undeployed position,distal end 478 has a cross-sectional dimension, length, and angularorientation α with respect to the longitudinal axis of the sheath 482and the longitudinal axis of the body 472 of instrument 470, which areselected to facilitate insertion of distal end 478 into a confinedsurgical operating space for a particular surgical procedure, asdiscussed previously. For example, for arthroscopy, at least onecross-sectional dimension of distal end 478, when in the undeployedconfiguration, should be no greater than about 2.8 mm, the length ofdistal end 478 is preferably between 10 and 15 mm, and angle α ispreferably about 15 degrees. Pressure lumen 488 is fixably mountedwithin body 472, so that it is essentially immobile with respect to body472, and is rotatably mounted within sheath 482 and rotatably mountedcomponent 480 so that the sheath can rotate around the outer surface ofthe pressure lumen upon deployment of distal end 478. By contrast,evacuation lumen 490 is fixably mounted to sheath 482 and/or rotatablymounted component 480, but is rotatably moveable within body 472 uponrotation of rotatably mounted component 480, so that rotation ofrotatably mounted component 480 and sheath 482 causes a correspondingrotation of evacuation lumen 490 resulting in deployment of distal end478. Rotatably mounted component 480 includes a slot or groove 492having a longitudinal axis 494 that is non-parallel with respect to thelongitudinal axis of rotatably mounted component 480 and thelongitudinal axis of body 472 of instrument 470. Slot 492 is used tocreate rotation of rotatably mounted component 480 upon movement ofslidable sleeve 476, as described in more detail below. Rotatablymounted component 480 also includes a bearing flange 496 which ismounted within body 472 of instrument 470 to allow for rotation ofcomponent 480, as described in more detail below. Deployment of distalend 478, as shown in FIG. 11c, establishes a separation distance lbetween jet opening 498 in nozzle 500 and jet-receiving opening 502 atthe distal end of evacuation lumen 490. Separation distance l defines aliquid jet path length, when the instrument is in operation. In certainpreferred embodiments, axis 504 which defines the direction of a centralregion of the liquid jet emitted from jet opening 498 when theinstrument is in operation, is non-parallel with respect to thelongitudinal axes of sheath 482 and body 472 of instrument 470.Typically, for such embodiments, axis 504 forms an angle with respect tothe longitudinal axis of body 472 that is between about 45 and 115degrees, more typically between about 80 and about 100 degrees, and mosttypically about 90 degrees.

[0147]FIG. 11d shows a partially cutaway view of surgical instrument 470showing more clearly the proximal end of body 472 and the connection ofpressure lumen 488 to high pressure liquid supply conduit 506 andevacuation lumen 490 to evacuation conduit 510. Pressure lumen 488 canbe connected to high pressure liquid supply conduit 506 via a highpressure tubing connector 508 as previously described. Pressure lumen488 and/or high pressure liquid conduit 506 are fixably mounted withinbody 472 to prevent movement of pressure lumen 488 with respect to body472 during deployment. Evacuation lumen 490 rotates within body 472 uponmovement of actuating element 476. Evacuation lumen 490 is connected toevacuation conduit 510, which is flexible and/or twistable within body472, to allow evacuation lumen 490 to rotate.

[0148] The actuating mechanism by which actuating element 476 causesrotation of rotatably mounted component 480 and sheath 482, in order todeploy distal end 478 of instrument 470, is shown more clearly in FIGS.11e and 11 f. Referring to FIG. 11e, a cut away view of actuatingelement 476 is shown. Actuating element 476 can be generally cylindricalin shape and includes two apertures 512 and 514. Aperture 512 is locatedon the proximal surface of actuating element 476 and allows actuatingelement 476 to accommodate body 472 of instrument 470. Aperture 514 islocated on the distal surface of actuating element 476 and has acircumference that is nearly equal or slightly greater than the outercircumference of rotatably mounted component 480, thus allowingrotatably mounted component 480 to pass through, and rotate within,aperture 514. Bearing flange 496 of rotatably mounted component 480 isrotatably mounted within bearing slots 516 of body 472. Shown in FIG.11f, actuating element 476 includes a pin 518 mounted within aperture514. As shown more clearly in FIG. 11e, when assembled, pin 518 fitswithin slot 492 of rotatably mounted component 480 so that as anoperator slides actuating element 476 in the direction of arrow 520, pin518 slides forward in slot 492 causing rotation of rotatably mountedcomponent 480 in the direction shown by arrow 522, thus causingdeployment of the distal end of instrument 470.

[0149]FIGS. 12a-12 e show an alternative embodiment for a rotatablydeployable surgical liquid jet instrument according to the invention.Referring to FIG. 12a, surgical instrument 530 is shown, which has abody 532 including an outer body component 534 with an external surface536 that acts as a grasping region, and an internal body component 538,which is slidably mounted within outer body component 534. Inner bodycomponent 538 includes two actuating elements 540, 542, each of whichmay be actuated by the hand of an operator holding grasping region 536.By sliding either actuating element in the direction indicated by arrows544 and 546, the operator can create a rotational movement of rotatablymounted component 548 and sheath 550 in the direction indicated by arrow552. Actuating elements 540 and 542 are positioned with respect tograsping region 536 so that the operator is able to hold body 532 of theinstrument in at least two different hand/grasping region orientations,while being able to access at least one of actuating elements 540 or 542in either hand/grasping region orientations. This configuration isparticularly advantageous when the instrument is designed forarthroscopic use in the knee or the shoulder.

[0150] The internal components of surgical instrument 530 are shown moreclearly in the cross-sectional views of FIGS. 12b-12 e. As shown in FIG.12b, rotatably mounted component 548 includes bearing flange 554 at itsproximal end. Bearing flange 554 is rotatably mounted within bearingslots 556, which are connected to outer body component 534 as shown moreclearly in FIG. 12d. Rotatably mounted component 548 extends distallyfrom bearing slots 556 through aperture 558 in actuating element 540.Actuating element 540 includes a pin 560 which traverses slot 562 inrotatably mounted component 548 when instrument 530 is assembled(similar to the configuration shown previously in FIG. 11e). Thus, bysliding inner body component 538 with respect to outer body component534 via actuating elements 540 or 542, the operator can slide pin 560within slot 562 causing rotation of rotatably mounted component 548 andsheath 550. In the embodiment shown, pressure lumen 564 is fixablymounted within body 532, but is free to rotate within rotatably mountedcomponent 548 and sheath 550. Evacuation lumen 566, by contrast, isfixably attached to sheath 550 and/or rotatably mounted component 548,so that evacuation lumen 566 rotates with respect to body 532 uponrotation of rotatably mounted component 548 and sheath 550, in order todeploy the distal end of instrument 530. In order to enable evacuationlumen 566 to rotate within body 532, evacuation lumen 566 is coupled atits proximal end 568 to a flexible/twistable evacuation conduit 570.Pressure lumen 564 is coupled to high pressure conduit 572 via highpressure connector 574, as previously discussed. High pressure conduit572 and evacuation conduit 570 are immobilized within body 532 viatubing holder elements 576, which are connected to outer body component534 as shown most clearly in FIG. 12c. As shown most clearly in FIG.12e, outer body component 534 and inner body component 538 are hollowand concentric, and have complementary shapes to allow the components toslide easily relative to one another. Preferably, outer body component534 and inner body component 538 have complementary shapes that allowfor relative longitudinal motion (sliding) of the components, but whichprevent relative rotational movement. In the illustrated embodiment,relative rotation is prevented by planar inner surfaces 577 of outerbody component 534 and planar outer surfaces 579 of inner body component538. As would be apparent to those of ordinary skill in the art, manyalternative shapes for the outer body component and the inner bodycomponent are possible that allow the components to slide relative toeach other while preventing relative rotation of the components, all ofwhich are within the scope and spirit of the invention.

[0151] In preferred embodiments, outer body component 534 and inner bodycomponent 538 comprise components that are injection molded from alightweight, inexpensive, and durable polymeric material. The componentsmay be manufactured as two symmetrical halves (e.g., halves 582 and 584of outer body component 534), which may be connected together uponassembly of instrument 530. Connection points between the halves of thecomponents, shown as 578 and 580, can be snap-fit joints, or may beconnected together via screws, clips, clamps, tape, adhesives, solventfusing, or any other suitable means of attachment as apparent to thoseof ordinary skill in the art.

[0152]FIG. 13 shows an exploded view of a surgical instrument 600 thatis similar in construction and operation to surgical instrument 530shown in FIG. 12a. Surgical instrument 600 includes a rotatably mountedcomponent 602 having a bearing sheath 604 which is rotatably mountedwithin a bearing slot formed by component 606 on outer body componenthalf 608 and a similar component on outer body component half 610 (notvisible). When instrument 600 is assembled, bearing flange 604 will passthrough windows 612 and 614 within inner body component halves 616 and618 to allow it to engage with the bearing slot components 606 on theouter body halves 608, 610. Inner body component half 618 also includespin 620 mounted therein which traverses slot 622 on rotatably mountedcomponent 602 when instrument 600 is assembled. When instrument 600 isassembled, the inner body component is able to slide within the outerbody component over a range of motion defined by the length of slot 622on rotatably mounted component 602. Movement of the inner body componentand rotation of rotatably mounted component 602 can be effected by anoperator holding instrument 600, via actuating elements 624, located atthe distal end of the inner body component, and/or actuating elements626, located at the proximal end of the inner body component.

[0153] Various components can be included as part of the outer bodycomponent and/or inner body component that are useful for supporting thepressure lumen, evacuation lumen, and rotatably mounted component 602within the body. For example, tubing support component 628 on outer bodycomponent half 608 can interact with a complementary component on outerbody component half 610 to support and immobilize the pressure andevacuation lumen/conduits, when instrument 600 is assembled. Similarly,sheath support components 630 on inner body component halves 616 and618, and sheath support components 632 on outer body component halves608 and 610 act to support and properly position rotatably mountedcomponent 602 when instrument 600 is assembled. Inner body componenthalf 616 also includes dowel elements 633 and dowel receptacle elements635, which are sized and shaped to securely fit together, that mate withcomplementary elements (not shown) on inner body component half 618 uponassembly of the instrument. Similarly, outer body component half 608includes flanges 632, which are sized and positioned to mate withcomplementary slots (not shown) on outer body component half 610, uponassembly, to improve the security of the connection of the componenthalves and durability of the body after assembly. Preferably, thecomponent halves of the inner and outer body components are furthersecured together by gluing, solvent bonding, ultrasonic welding, orpress fitting, but may, in other embodiments, be secured by a variety ofmeans apparent to those of ordinary skill in the art including, but notlimited to, screws, clips, clamps, straps, etc.

[0154] It should be understood that the above mentioned mechanicalactuation mechanisms for the inventive surgical instruments are purelyexemplary, and that modifications to the above-mentioned mechanisms, oralternative ways of deploying the distal ends of the inventive surgicalinstruments to provide a separation distance defining a liquid jet pathlength may be envisioned by those of ordinary skill in the art, and thatsuch modifications, or alternative mechanisms are within the scope andspirit of the present invention, as described and defined by theappended claims. For example, for the embodiments shown in FIGS. 11a-11f, instead of employing an actuating element having a pin, and arotatably mounted component having a groove in which the pin slides uponsliding the actuating element, in other embodiments, the actuatingelement may instead be rigidly attached to the rotatably mountedcomponent, so that rotation of the rotatably mounted component iseffected by rotation of the actuating element by the operator. In yetother embodiments, instead of employing actuating components comprisingslidable sleeves, or body components that are slidable relative to oneanother as shown in FIGS. 11a-11 f and FIGS. 12a-12 e, alternatively,the actuating element may comprise one or more slidable levers, orrotatable knobs, having a pin attached thereto, within the body of thedevice.

[0155] The deployable surgical instruments described above areespecially useful for performing surgical procedures in confined regionsinternally of a body defining a confined surgical operating space. Asdiscussed previously, the distal ends of the instruments are providedwith a contour in size that is specifically selected to facilitateinserting the distal end of the surgical instruments into the confinedregions, when the instrument is in an undeployed configuration.Accordingly, the inventive instruments enable the performance of novelsurgical methods utilizing the inventive instruments. For example, thedeployable surgical liquid jet instruments described above may beadvantageously employed for use in a surgical method involving thecutting or ablating of a selected tissue within the joint capsule of apatient. The method comprises inserting a surgical-liquid jetinstrument, provided by the invention, and having a distal endspecifically designed for the surgical procedure, into the joint capsuleof the patient. Upon insertion of the instrument into the joint capsule,the operator of the instrument can then deploy the distal end of theinstrument to create a separation distance between the jet opening andthe jet-receiving opening, defining a liquid jet path length. Theoperator can then turn on a pump or dispenser supplying high pressureliquid to the device, as discussed previously, in order to create aliquid jet with the surgical instrument. The liquid jet can then bedirected towards the jet receiving opening in the evacuation lumen ofthe instrument, and will tend to create an entrainment regionsurrounding the liquid jet, which can be effective for cutting orablating a selected tissue within the joint capsule.

[0156] In some procedures, the cutting or ablating of tissue cancomprise positioning the liquid jet nozzle in close proximity to a solidsurface within the joint capsule, for example the surface of a bone, anddirecting the liquid jet essentially parallel to the solid surface toremove selected tissue from the surface. Depending on the hardness andtoughness of the material to be removed from the surface, the liquidjet, in some instances, may need to be brought essentially adjacent tothe solid surface. For soft material, such as fatty tissue, the liquidjet need not be brought into direct contact with the material, or withthe solid surface containing the material, but rather, the entrainmentregion created by the liquid jet can draw the material from the surfacetowards the jet in order to cut and/or ablating the material andevacuate the material through the evacuation lumen. For very hardtissue, such as bone or cartilage, the liquid jet entrainment region mayneed to be brought into essentially direct contact with the material tobe cut and/or ablated. Advantageously, preferred surgical instrumentsaccording to the invention are capable of performing the above mentionedsurgical procedures and evacuating ablated material, blood, and debrisfrom the surgical operating space without requiring an external sourceof suction. The above mentioned instruments, because of theireffectiveness in removing material from the operating space, can providea surgical operating field providing excellent visibility for theoperator performing the surgical procedure.

[0157] A representative procedure, meniscectomy of a human knee,employing the inventive fluid jet cutting system is describedimmediately below. First, the patient to be operated on is anesthetizedand a tourniquet is applied the thigh of the leg and set to a pressureof about 280 mm Hg. The patient is then prepped and draped in theconventional manner. Saline is introduced into the knee either through asuperior medial portal, using an inflow canula, or through a scopecanula placed in the lateral portal at the joint line. Saline can exitthe knee cavity out of the medial portal at the joint line. Thepathology of the knee can be visualized through use of an endoscopiccamera. After bending the knee, valgus or varus stress is applied tofacilitate the approach to tight compartments within the joint capsule.The inventive surgical liquid jet instrument is then inserted, in theundeployed configuration, through one of the portal. As discussed above,the profile and contour of the distal end of the instrument is designedspecifically for facilitating access into the confined regions of theknee anatomy, and to provide a proper cutting orientation during use.Specifically, upon insertion into the joint cavity of the knee, while inthe undeployed position, the surgical instrument is configured to passthrough the tight gap between the condyle and the tibial plateau, sothat the instrument may be deployed after it is properly positioned atthe posterior meniscus site. While in operation, the instrument breaksup ablated or cut tissue into small, and preferably microscopicfragments and evacuates it from the knee, without the need for externalsuction, through the evacuation lumen. After completing the surgery, thefluid jet instrument and visualization endoscope can be removed from theportals and the knee can be drained and wrapped.

[0158] Surgical liquid jet instruments according to the invention canalso be used for operative procedures in other joint capsules of apatient, for example, the human shoulder. For certain procedures, forexample, acromioplasty within the shoulder, which can involve asignificant amount of bleeding, it is contemplated that the surgicalinstruments provided according to the invention can be utilized inconjunction with electrocautery in order to reduce bleeding caused bythe surgical procedure.

[0159]FIG. 14a and 14 b show an alternative embodiment for a surgicalliquid jet instrument according to the invention. The embodiment shownin FIG. 14a and 14 b is particularly advantageous for use in proceduresin a surrounding air environment involving debriding or ablating amaterial from an external surface of the body of a patient. Instrument650 includes body 652 having a grasping portion 654 configured to beheld in the hand of an operator. Extending distally from body 652 is asheath 656, which extends distally to the extreme distal point 658 ofinstrument 652, and essentially completely surrounds pressure lumen 660and evacuation lumen 662, (shown most clearly in FIG. 14b). As shown inFIG. 14b, pressure lumen 660 includes two jet nozzles 664 and 666comprising holes bored in the sidewall of the pressure lumen 660. Eachof nozzles 664 and 666 creates a diverging liquid jet, which is directedinto jet receiving opening 668 at the distal end of evacuation lumen662, as described previously. In alternative embodiments, evacuationlumen 662 may include only a single nozzle. The liquid jets emitted fromnozzle 664 and 666 have central regions that are directed essentiallyparallel to the longitudinal axes of evacuation lumen 662, sheath 656,and body 652. In alternative embodiments, sheath 656, instead of beingstraight as illustrated, can be curved or angled near the distal end inorder to provide a more advantageous ergonomic shape for certainsurgical procedures (for example, see FIG. 2b).

[0160] In use, the surgical instrument according to the invention asillustrated in FIGS. 14a and 14 b, can be utilized in a surgicalprocedure for debriding material from the skin, or external body surfaceof a patient. Such a surgical method involves positioning the inventivesurgical liquid jet instrument in close proximity to an external surfaceon the body of a patient, and then creating a liquid jet by supplying ahigh pressure fluid to the instrument, so that at least a portion of thejet is directed essentially parallel to the surface of the body and sothat essentially the entire jet is directed towards the jet-receivingopening in the evacuation lumen. The entrainment region created by theliquid jet, as discussed above, can be used to debride or ablate amaterial from the surface of the patient and evacuate the material,along with the liquid comprising the liquid jet, from the jet-receivingopening and through the evacuation lumen, preferably without utilizingan external source of suction. The method may be advantageously employedfor cleaning wounds, surgical incisions, sites of infection, etc. Thedebrided material may comprise one or more of living tissue, deadtissue, or organic/inorganic foreign matter that may be embedded in thesurface prior to debriding the surface with the instrument.

[0161] While several embodiments of the invention have been describedand illustrated herein, those of ordinary skill in the art will readilyenvision a variety of other means and structures for performing thefunctions and/or obtaining the results or advantages described herein,and each of such variations or modifications is deemed to be within thescope of the present invention. More generally, those skilled in the artwould readily appreciate that all parameters, dimensions, materials, andconfigurations described herein are meant to be exemplary and thatactual parameters, dimensions, materials, and configurations will dependupon specific applications for which the teachings of the presentinvention are used. Those skilled in the art will recognize, or be ableto ascertain using no more than routine experimentation, manyequivalents to the specific embodiments of the invention describedherein. It is, therefore, to be understood that the foregoingembodiments are presented by way of example only and that, within thescope of the appended claims and equivalents thereto, the invention maybe practiced otherwise than as specifically described. The presentinvention is directed to each individual feature, system, materialand/or method described herein. In addition, any combination of two ormore such features, systems, materials and/or methods, provided thatsuch features, systems, materials and/or methods are not mutuallyinconsistent, is included within the scope of the present invention. Inthe claims, all transitional phrases or phrases of inclusion, such as“comprising,” “including,” “carrying,” “having,” “containing,” “composedof,” “made of,” “formed of” and the like are to be understood to beopen-ended, i.e. to mean “including but not limited to.” Only thetransitional phrases or phrases of inclusion “consisting of” and“consisting essentially of” are to be interpreted as closed orsemi-closed phrases, respectively, as set forth in MPEP section 2111.03.

What is claimed is:
 1. A device for use in a gaseous environment,comprising: a surgical instrument having a distal end adapted to performa surgical procedure on a patient and a proximal end adapted to becontrollable by an operator, the instrument comprising a pressure lumenhaving sufficient burst strength to conduct a high pressure liquidtowards the distal end of the instrument, the pressure lumen includingat least one nozzle providing a jet opening; and an evacuation lumenincluding a jet-receiving opening locatable opposite the jet opening, ata predetermined distance therefrom, to receive a liquid jet when theinstrument is in operation; wherein the nozzle is shaped to form aliquid jet, as a liquid at high pressure flows therethrough, the liquidjet comprising a diverging region of liquid droplets moving through thegaseous environment, with the diverging region having an apex located atthe jet opening, such that essentially all of the moving liquid dropletsin the diverging region are directed into the jet-receiving opening whenthe instrument is in operation.
 2. A device as in claim 1, wherein theevacuation lumen is shaped and positionable to enable evacuation ofessentially all of the liquid comprising the liquid jet from thejet-receiving opening to a proximal end of the evacuation lumen withoutthe need for an external source of suction.
 3. A device as in claim 1,wherein the pressure lumen includes at least two nozzles each providinga jet opening.
 4. A device as in claim 1, wherein the nozzle and thejet-receiving opening are shaped and positionable relative to each otherso that back flow of a spray or a liquid mist from the jet-receivingopening into the gaseous environment is essentially eliminated when theinstrument is in operation.
 5. A device as in claim 1, wherein thenozzle and the jet-receiving opening are shaped and positionablerelative to each other so that a cross-sectional shape and area of theliquid jet at a given location within the evacuation lumen, the givenlocation being at least one of the jet-receiving opening and a locationproximal to the jet-receiving opening, is essentially the same as aninternal cross-sectional shape and area of the evacuation lumen at thegiven location, when the instrument is in operation.
 6. A device as inclaim 1, wherein the instrument includes a sheath surrounding at least aportion of the pressure lumen and the evacuation lumen.
 7. A device asin claim 6, wherein the sheath is essentially straight with alongitudinal axis that is essentially parallel to a longitudinal axis ofthe proximal end of the surgical instrument.
 8. A device as in claim 6,wherein the sheath has a proximal and a distal region and is at leastone of curved and angled in the distal region of the sheath.
 9. A deviceas in claim 1, wherein an axis defining a direction of at least acentral region of the liquid jet and a longitudinal axis of the proximalend of the surgical instrument are essentially parallel when theinstrument is in operation.
 10. A device as in claim 1, wherein an axisdefining a direction of at least a central region of the liquid jet anda longitudinal axis of the proximal end of the surgical instrument arenon-parallel to each other when the instrument is in operation.
 11. Adevice as in claim 1, wherein the diverging region of liquid dropletshas a truncated cone shape.
 12. A device as in claim 1, wherein thenozzle has a region of minimum cross-sectional diameter having apredetermined length, the ratio of the predetermined length to theminimum cross-sectional diameter being not greater than about four. 13.A device as in claim 12, wherein the ratio of the predetermined lengthto the minimum cross-sectional diameter is not greater than about two.14. A device as in claim 1, further comprising a body that includes agrasping region shaped and positionable to be held by a hand of theoperator.
 15. A device as in claim 1, wherein the surgical instrument isconstructed and arranged to be entirely disposable after a single use.16. A device for use in a gaseous environment, comprising: a surgicalinstrument having a distal end adapted to perform a surgical procedureon a patient and a proximal end adapted to be controllable by anoperator, the instrument comprising a pressure lumen having sufficientburst strength to conduct a high pressure liquid towards the distal endof the instrument, the pressure lumen including at least one nozzleproviding a jet opening; and an evacuation lumen having a proximal endand a distal end, the distal end including a jet-receiving openinglocatable opposite the jet opening at a predetermined distance therefromto receive the liquid jet when the instrument is in operation; whereinthe evacuation lumen is shaped and positionable to enable evacuation ofessentially all of the liquid comprising the liquid jet from thejet-receiving opening to the proximal end of the evacuation lumenwithout the need of an external source of suction.
 17. A device as inclaim 16, wherein the surgical instrument is constructed and arranged tobe entirely disposable after a single use.
 18. A device as in claim 16,wherein the pressure lumen includes at least two nozzles each providinga jet opening.
 19. A device as in claim 16, wherein the nozzle and thejet-receiving opening are shaped and positionable relative to each otherso that back flow of a spray or a liquid mist from the jet-receivingopening into the gaseous environment is essentially eliminated when theinstrument is in operation.
 20. A device as in claim 16, wherein thenozzle and the jet-receiving opening are shaped and positionablerelative to each other so that a cross-sectional shape and area of theliquid jet at a given location within the evacuation lumen, the givenlocation being at least one of the jet-receiving opening and a locationproximal to the jet-receiving opening, is essentially the same as aninternal cross-sectional shape and area of the evacuation lumen at thegiven location, when the instrument is in operation.
 21. A device as inclaim 16, further comprising a body that includes a grasping regionshaped and positionable to be held by a hand of the operator.
 22. Amethod comprising: inserting a surgical liquid-jet instrument into ajoint capsule of a patient; creating a liquid jet with the surgicalliquid-jet instrument; directing the liquid jet towards a jet-receivingopening in an evacuation lumen of the surgical liquid-jet instrument;and cutting or ablating a selected tissue within the joint capsule withthe liquid jet.
 23. A method as in claim 22, wherein the joint capsulecomprises a human knee and the selected tissue comprises posteriormeniscus tissue.
 24. A method as in claim 22, wherein the joint capsulecomprises a human shoulder.
 25. A method as in claim 22, wherein duringthe inserting step, the surgical liquid-jet instrument is in anundeployed configuration and after the inserting step and before thecreating step, the surgical liquid-jet instrument is deployed to createa separation distance between a jet opening from which the liquid jetemerges and the jet-receiving opening, the separation distance defininga path length for the liquid jet.
 26. A method as in claim 22, whereinthe cutting or ablating step comprises positioning a section of tissuein contact with an entrainment zone of moving liquid surrounding theliquid jet.
 27. A method as in claim 22, wherein the cutting or ablatingstep comprises positioning a jet opening, from which the liquid jetemerges, in close proximity to a solid surface within the joint capsule,directing the liquid jet essentially tangential to the solid surface,and removing the selected tissue from the surface.
 28. A method as inclaim 22, wherein the cutting or ablating step comprises positioning ajet opening, from which the liquid jet emerges, adjacent to a solidsurface within the joint capsule, directing the liquid jet essentiallytangential to the solid surface, and removing the selected tissue fromthe surface.
 29. A method as in claim 22, further comprising removingliquid comprising the liquid jet and the selected tissue from the jointcapsule without applying a source of external suction in fluidcommunication with the evacuation lumen.
 30. A method comprising:positioning a surgical liquid-jet instrument in close proximity to asurface of a body of a patient; creating a liquid jet in a surroundinggaseous environment with the surgical liquid-jet instrument; directingthe liquid jet essentially tangential to the surface and towards ajet-receiving opening in an evacuation lumen; debriding a material fromthe surface with the liquid jet; and evacuating a liquid comprising theliquid jet and the debrided material from the jet-receiving opening to aproximal end of the evacuation lumen without the need for an externalsource of suction.
 31. A method as in claim 30, wherein the surface of abody of a patient comprises an external body surface.
 32. A method as inclaim 31, wherein the external body surface at least partially compriseshuman skin.
 33. A method as in claim 30, wherein at least a portion ofthe material debrided during the debriding step comprises at least oneof living tissue and dead tissue.
 34. A method as in claim 30, whereinat least a portion of the material debrided during the debriding stepcomprises foreign matter embedded in the surface prior to the debridingstep.
 35. A device comprising: a surgical instrument having a distal endadapted to perform a surgical procedure on a patient and a proximal endincluding a body, the body having a grasping region shaped andpositionable to be held by a hand of an operator, the instrumentcomprising: a pressure lumen having sufficient burst strength to conducta high pressure liquid towards the distal end of the instrument, thepressure lumen including at least one nozzle providing a jet opening;and an evacuation lumen including a jet-receiving opening locatableopposite the jet opening at a predetermined distance therefrom toreceive a liquid jet when the instrument is in operation; wherein atleast one nozzle comprises a hole in a side wall of a lumen.
 36. Adevice as in claim 35, wherein the evacuation lumen includes a regionwithin and adjacent to the jet-receiving opening, the evacuation lumenbeing shaped so that a liquid within the region is able to macerate atleast a portion of a tissue entrained in the liquid into a plurality ofparticles when the instrument is in operation.
 37. A device as in claim35, wherein the nozzle is shaped to form a liquid jet as a liquid athigh pressure flows therethrough and the liquid jet and the evacuationlumen are shaped and positionable such that a substantial fraction of atissue entrained by the liquid jet is reduced to a plurality ofmicroscopic particles when the instrument is in operation.
 38. A deviceas in claim 35, wherein at least a portion of the pressure lumen and atleast a portion of the evacuation lumen are movable relative to eachother to enable adjustment of a separation distance between the jetopening and the jet-receiving opening.
 39. A device as in claim 35,wherein the evacuation lumen has an internal cross-sectional area whichincreases continuously from a minimum value at the jet-receiving openingto a maximum value at a predetermined position proximal to thejet-receiving opening, which maximum value is essentially constant atpositions proximal to the predetermined position.
 40. A device as inclaim 35, wherein the evacuation lumen is shaped and positionable toenable evacuation of essentially all of the liquid comprising the liquidjet from the jet-receiving opening to a proximal end of the evacuationlumen without the need for an external source of suction.
 41. A deviceas in claim 35, wherein the surgical instrument is constructed andarranged to be entirely disposable after a single use.
 42. A device asin claim 35, wherein the surgical instrument is constructed and arrangedto be operated in a gaseous environment, where at least one of the jetopening and the jet-receiving opening are essentially entirelysurrounded be a gas when the instrument is in operation.
 43. A methodcomprising: necking down an end of a tube providing a lumen to form ajet nozzle region in the tube having a reduced cross-sectionaldimension; and offsetting the jet nozzle region from being essentiallyco-linear with an axial centerline of the tube outside the jet nozzleregion to a position where an axial centerline of the jet nozzle regionis displaced from the axial centerline of the tube outside the jetnozzle region by a distance of about d=R−r, where R is the internalradius of the tube outside the jet nozzle region and r is the internalradius of the jet nozzle region.
 44. A method as in claim 43, whereinthe method further comprises the step of bending the offset jet nozzleregion so that the axial centerline of the jet nozzle region isnon-parallel to the axial centerline of the tube outside the jet nozzleregion.
 45. A method as in claim 44, wherein the axial centerline of thejet nozzle region forms an angle with the axial centerline of the tubeoutside the jet nozzle region of about 90 degrees.
 46. A method as inclaim 44, wherein essentially no portion of the jet nozzle regionprojects radially beyond a perimeter defined by an outer surface of thetube outside the jet nozzle region.
 47. A device for use in an gaseousenvironment, comprising: a surgical instrument having a distal endadapted to perform a surgical procedure on a patient and a proximal endadapted to be controllable by an operator, the instrument comprising: apressure lumen having sufficient burst strength to conduct a highpressure liquid towards the distal end of the instrument, the pressurelumen having a distal end including at least two nozzles, each providinga jet opening, each nozzle shaped to form a liquid jet as a liquid athigh pressure flows therethrough; and an evacuation lumen having adistal end including a jet-receiving opening locatable opposite at leastone of the jet openings, at a predetermined distance therefrom, thedistance defining a gas-filled gap between the jet opening and thejet-receiving opening, the jet-receiving opening shaped and positionableto receive at least one liquid jet when the instrument is in operation.48. A device as in claim 47, wherein the jet-receiving opening is shapedand positionable to receive each liquid jet when the instrument is inoperation.
 49. A device as in claim 47, wherein the evacuation lumen isshaped and positionable to enable evacuation of essentially all of theliquid comprising at least one liquid jet from the jet-receiving openingto a proximal end of the evacuation lumen without the need for anexternal source of suction.
 50. A device as in claim 48, wherein theevacuation lumen is shaped and positionable to enable evacuation ofessentially all of the liquid comprising each liquid jet from thejet-receiving opening to a proximal end of the evacuation lumen withoutthe need for an external source of suction.
 51. A device for use in agaseous environment, comprising: a surgical instrument having a distalend adapted to perform a surgical procedure on a patient and a proximalend adapted to be controllable by an operator, the instrumentcomprising: a pressure lumen having sufficient burst strength to conducta high pressure liquid towards the distal end of the instrument, thepressure lumen including at least one nozzle providing a jet opening;and an evacuation lumen including a jet-receiving opening locatableopposite the jet opening at a predetermined distance therefrom toreceive a liquid jet when the instrument is in operation; wherein thenozzle is shaped to form a liquid jet as a liquid at high pressure flowstherethrough, the liquid jet being directed across an gas-filled gap andinto the jet-receiving opening when the instrument is in operation, andthe nozzle and the jet-receiving opening are shaped and positionablerelative to each other so that back-flow of a liquid mist or spray fromthe jet-receiving opening into the gas-filled gap is essentiallyeliminated when the instrument is in operation.
 52. A device as in claim51, wherein the nozzle and the jet-receiving opening are shaped andpositionable relative to each other so that a cross-sectional shape andarea of the liquid jet at a given location within the evacuation lumen,the given location being at least one of the jet-receiving opening and alocation proximal to the jet-receiving opening, is essentially the sameas an internal cross-sectional shape and area of the evacuation lumen atthe given location, when the instrument is in operation.
 53. A devicefor use in a gaseous environment, comprising: a surgical instrumenthaving a distal end adapted to perform a surgical procedure on a patientand a proximal end adapted to be controllable by an operator, theinstrument comprising: a pressure lumen having sufficient burst strengthto conduct a high pressure liquid towards the distal end of theinstrument, the pressure lumen including at least one nozzle providing ajet opening; and an evacuation lumen including a jet-receiving openinglocatable opposite the jet opening at a predetermined distance therefromto receive a liquid jet when the instrument is in operation; wherein thenozzle is shaped to form a liquid jet as a liquid at high pressureliquid flows therethrough, the liquid jet being directed across agas-filled gap and into the jet-receiving opening when the instrument isin operation, and the nozzle and the jet-receiving opening are shapedand positionable relative to each other so that a cross-sectional shapeand area of the liquid jet at a given location within the evacuationlumen, the given location being at least one of the jet-receivingopening and a location proximal to the jet-receiving opening, isessentially the same as an internal cross-sectional shape and area ofthe evacuation lumen at the given location, when the instrument is inoperation.
 54. A device as in claim 53, wherein the given location isthe jet-receiving opening.
 55. A device as in claim 53, wherein thegiven location is the no greater than about 5 mm proximal to thejet-receiving opening.